Perform multipath communication

Abstract

A method for performing multipath communication at a target communication device, the method comprising: obtaining multiple data messages from a source communication device through two or more different paths, wherein the header of each data message includes message information indicating the association between the multiple data messages. The message information in each data message of the source communication device is the same as the message information in each data message of the target communication device, regardless of which radio access technology, communication protocol or wireless link is used by the two or more different paths. The multiple data messages include different data messages with different payloads or duplicate data messages with the same payload copy. The method also includes identifying a first group of data messages received through a first path and a second group of data messages received through a second path based on the message information.

Description

Technical Field

[0001] The present invention generally relates to the field of wireless communication technology; more particularly, to a method and apparatus for performing multipath communication. Background Art

[0002] Currently, there are many wireless communication technologies that can be used to communicate between two communication devices. In some cases, the communication of data packets between two communication devices may be interrupted or data may be lost, the throughput may be low and / or there may be delays. For example, in device-to-device communication, one communication device may move out of the communication range of another communication device, resulting in interruption of data communication. In another example, cellular communication can be used to communicate between two communication devices. Typically, cellular networks provide a larger coverage area than device-to-device communication. However, the sequence numbers of data packets received through the uplink and downlink in cellular communication may be different, or the data packets may be out of order, resulting in data errors. Therefore, the reception of data packets on the destination device may be unreliable, inefficient or delayed. Typically, next-generation services (e.g., Internet of Vehicles services) have stringent quality of service requirements, which may be difficult to meet using traditional wireless communication methods and systems.

[0003] Therefore, in light of the foregoing discussion, a need exists to overcome the aforementioned shortcomings associated with conventional systems and methods for wireless communication of data packets. Summary of the invention

[0004] The present invention seeks to provide methods, apparatus and computer program products for performing multipath communications. The present invention is intended to provide a solution to the existing problems of inefficient and unreliable wireless communication of data between at least two communication devices. The purpose of the present invention is to provide a solution that at least partially overcomes the problems encountered in the prior art and provides an improved method and apparatus that can efficiently and reliably send data messages.

[0005] The objects of the invention are achieved by what is presented in the attached independent claim. Advantageous implementations of the invention are further defined in the dependent claims.

[0006] In a first aspect, the present invention provides a method for performing multipath communication at a target communication device. The method includes obtaining multiple data packets from a source communication device through two or more different paths, wherein the header of each data packet in the multiple data packets includes message information. The message information indicates the association between the multiple data packets. The message information in each data packet of the source communication device is the same as the message information in each data packet of the target communication device, regardless of which wireless access technology, communication protocol or wireless link is used by the two or more different paths. The multiple data packets include different data packets with different loads or duplicate data packets with the same load copy. The method also includes: according to the message information, identifying a first group of data packets in the multiple data packets received through the first path and a second group of data packets in the multiple data packets received through the second path.

[0007] The method of the first aspect can realize the acquisition of multiple data messages through two or more different paths, and further identify which path in the two or more different paths receives which data messages. Since the message information in the header of each data message does not change, no matter which radio access technology, communication protocol or wireless link is used by two or more different paths, the method can realize the establishment of correlation between multiple data messages transmitted in a multipath environment. The method improves the quality of service (quality-of-service, QoS) of data communication between a source communication device and a target communication device. For example, in the case where multiple data messages obtained through two or more different paths include different data messages with different loads, the method improves data throughput and reduces the delay of data communication between the source communication device and the target communication device. In the case where multiple data messages obtained through two or more different paths include duplicate data messages with the same load copy, the method improves the reliability of data communication between the source communication device and the target communication device.

[0008] In a first implementation manner of the first aspect, at least one of the first path and the second path corresponds to a device-to-device communication between the source communication device and the target communication device.

[0009] In device-to-device communication, at least one of the first set of data packets or the second set of data packets is received through a direct link between a source communication device and a target communication device, which reduces delay and improves flexibility of data communication.

[0010] In a second implementation of the first aspect, the first path among the two or more different paths is a cellular communication path, the second path among the two or more different paths is a sidelink communication path corresponding to the device-to-device communication, and the source communication device and the target communication device are at least one of the following: a vehicle, an electronic device used in a vehicle, or a portable electronic device.

[0011] The cellular communication path provides a large coverage area, while the sidelink communication path improves capacity and network performance through spatial frequency reuse. Therefore, multipath communication using cellular communication and sidelink communication can achieve enhanced and reliable communication between two communication devices.

[0012] In a third implementation manner of the first aspect, the method further includes: the target communication device filtering duplicate data packets from the multiple data packets received by the target communication device according to the packet information.

[0013] The filtering of the duplicate data messages ensures that the data is not duplicated when the data is finally presented on the target communication device.

[0014] In a fourth implementation manner of the first aspect, the method includes: the target communication device reorders the multiple data packets according to the message information and a sequence number associated with each of the multiple data packets, wherein, in a partitioning mode, the multiple data packets include different data packets obtained through the first path and the second path.

[0015] The reordering of the plurality of data messages by sequence number ensures that the data messages are reordered at the target communication device in the same order as the order in which the data messages were sent by the source communication device. Therefore, the method ensures complete data recovery at the target communication device with high reliability and avoids data loss.

[0016] In a second aspect, the present invention provides a method for performing multipath communication on a source communication device. The method comprises: providing a first group of data messages in a plurality of data messages to a target communication device via a first path and providing a second group of data messages in a plurality of data messages to the target communication device via a second path. The header of each data message comprises message information indicating an association between the plurality of data messages. The plurality of data messages comprises different data messages with different payloads or duplicate data messages with copies of the same payload.

[0017] The method improves the flexibility of data communication because two different paths are used to send different data messages with different payloads or duplicate data messages with the same payload copy. In the case where the second group of data messages provided through the second path are duplicate data messages with the same payload copy as the first group of data messages provided through the first path, the method improves the reliability of data communication between the source communication device and the target communication device by performing multipath communication. In addition, in the case where the first group of data messages are different data messages with different payloads from the second group of data messages, the method improves data throughput and reduces the delay of data communication between the source communication device and the target communication device by performing multipath communication.

[0018] In a first implementation manner of the second aspect, at least one of the first path or the second path corresponds to device-to-device communication between the source communication device and the target communication device, and wherein the message information in each data packet of the source communication device is the same as the message information in each data packet of the target communication device, regardless of which wireless access technology, communication protocol or wireless link is used by the two or more different paths.

[0019] In device-to-device communication, at least one of the first set of data packets or the second set of data packets received through a direct link between a source communication device and a target communication device is provided to the target communication device, which reduces delay and improves the flexibility of data communication. Since the message information in each data packet of the source communication device is the same as the message information in each data packet of the target communication device, regardless of which radio access technology, communication protocol or radio link is used by the first path and the second path, the method facilitates end-to-end tracking and correlation of data packets transmitted in a multi-path environment.

[0020] In a second implementation of the second aspect, the method includes: the source communication device selects a repetition mode or a division mode to send the multiple data packets to the target communication device through two or more different paths, wherein the repetition mode or the division mode is selected before the start of a data session or during a data session.

[0021] The decision to select a repeat mode or a split mode improves the flexibility of data communication. Specifically, selecting a repeat mode improves the reliability of data communication, while selecting a split mode improves throughput and reduces data communication latency. In addition, since it can be done before a data session begins or even during a data session, fail-safe communication is ensured.

[0022] In a third implementation of the second aspect, the method further includes: the source communication device sends the first group of data packets to the network entity through the first path in uplink transmission, and sends the second group of data packets to the target communication device through the second path as repeated data packets according to the selected repetition mode, wherein in the repetition mode, the load of the first group of data packets is the same as the load of the second group of data packets.

[0023] In the repetition mode, the payload of the first set of data messages is the same as the payload of the second set of data messages, which ensures that all data messages sent by the source communication device are reliably received at the target communication device, and the risk of any data loss due to, for example, signal fading is significantly reduced.

[0024] In a fourth implementation of the second aspect, the method further includes: the source communication device sends the first group of data packets to the network entity through the first path in uplink transmission, and sends the second group of data packets to the target communication device through the second path, wherein, in the division mode, the load of the first group of data packets is different from the load of the second group of data packets.

[0025] In the split mode, the payload of the first group of data messages is different from the payload of the second group of data messages, which ensures that the source communication device provides data to the target communication device at a faster rate than data messages transmitted through the repetition mode.

[0026] In a fourth implementation of the second aspect, a header of each of the plurality of data packets or a signaling message sent by the source communication device to at least one of the network entity or the target communication device when the data session is established or updated includes an indicator. The indicator indicates that a multipath function is enabled at the network entity or at the target communication device.

[0027] Activation lets a network entity (eg, a radio access network node or a core network entity) know that it must perform a specific function, such as retaining message information in the header of each received data message. The indicator enables end-to-end tracking and correlation of data messages transmitted in a multipath environment.

[0028] In a third aspect, the present invention provides a method for performing multipath communication at a network entity. The method comprises: obtaining a first group of data packets from a source communication device, wherein a header of each data packet in the first group of data packets comprises message information. The message information indicates an association between the first group of data packets. The method further comprises: mapping an uplink sequence number of each data packet in the received first group of data packets to a downlink sequence number according to the message information; and providing each received data packet in the first group of data packets including the message information to at least one of a target communication device or another network entity according to the mapping of the uplink sequence number to the downlink sequence number.

[0029] Mapping the uplink sequence number of each data message in the first group of data messages to the downlink sequence number solves the problem of out-of-order data messages. As a result of the mapping, there is no need to apply the traditional sequence number derivation method to the downlink data message. In addition, based on the message information and the mapping, the method can achieve end-to-end tracking and association of the first group of data messages obtained from the source communication device, and also provide it to the target communication device or another network entity (for example, another radio access network node or core network entity).

[0030] In a first implementation of the third aspect, the uplink sequence number is received from the source communication device in a designated network layer, and the uplink sequence number is mapped to the downlink sequence number in the designated network layer. The designated network layer is at least one of a packet data convergence protocol (PDCP) layer, a service data adaptation protocol (SDAP) layer, or other network layers.

[0031] The uplink sequence number of the specified network layer (eg, uplink PDCP sequence number) is retained and mapped to the downlink sequence number of the specified network layer (eg, downlink PDCP sequence number), thereby resolving the disorder problem of data messages and ensuring the correct ordering of these data messages.

[0032] In a second implementation of the third aspect, the method further includes: the network entity attaching the uplink sequence number received from the source communication device to the core network protocol-based header of each received data message in the first group of data messages. The method further includes: the network entity sending each received data message in the first group of data messages to the core network entity, each received data message in the first group of data messages having the core network protocol-based header including the attached uplink SN, wherein the core network protocol-based header including the attached uplink sequence number is a modified core network protocol-based header including the attached uplink sequence number, as an extension of the header structure of the core network protocol-based header.

[0033] In order to solve the problem of data message disorder and enable the target communication device to compare the data messages transmitted through the first path and the second path, the core network protocol-based header of each data message obtained by the network entity (i.e., the source network entity) is attached with the uplink sequence number obtained from the source communication device.

[0034] In a third implementation manner of the third aspect, the core network protocol-based header is a general packet radio service (GPRS) tunneling protocol user plane (GTP-U) header.

[0035] In conventional systems, the sequence numbers of data packets received via uplink and downlink in cellular communications may be different, or the data packets may become out of sequence (i.e., out of order). Therefore, by using a modified GTP-U header including an attached uplink sequence number, the out of sequence problem of data packets when the data packets are transmitted through a cellular network is solved.

[0036] In a fourth implementation of the third aspect, the method further includes: before the received data packets in the first group of data packets are downlinked to the target communication device, the network entity sets the retrieved uplink sequence number in each received data packet in the multiple data packets as the downlink sequence number.

[0037] Since the downlink sequence number of each data message is the same as the corresponding uplink sequence number, there is no need to apply the usual sequence number derivation method to the downlink data message, and reliable end-to-end tracking of the data message is ensured throughout the communication process.

[0038] In a fifth implementation of the third aspect, the method further includes: the network entity enabling a multipath function according to an indicator in the header of each data message in the first group of data messages or in a signaling message sent by the source communication device. Enabling the multipath function includes: storing the message information in each data message in the first group of data messages received by the network entity, and multiplexing the message information to further provide each received message to the target communication device; or routing each data message in the first group of data messages with the message information to another network entity, and the network entity multiplexing the message information to further provide each received message to the target communication device through the network entity or another network entity.

[0039] To enable the target communication device to compare and track data packets transmitted via the first path and the second path, the method can activate the multipath function on a per-data packet basis using an indicator in a header of each data packet or on a session level basis using a signaling message.

[0040] In a fourth aspect, the present invention provides a target communication device for performing multi-path communication. The target communication device includes: a control circuit, the control circuit is used to obtain multiple data messages from a source communication device through two or more different paths, wherein the header of each data message in the multiple data messages includes message information. The message information indicates the association between the multiple data messages. The message information in each data message of the source communication device is the same as the message information in each data message of the target communication device, regardless of which wireless access technology, communication protocol or wireless link is used by the two or more different paths. The multiple data messages include different data messages with different loads or duplicate data messages with the same load copy. The control circuit is also used to: identify a first group of data messages in the multiple data messages received through the first path and a second group of data messages in the multiple data messages received through the second path according to the message information.

[0041] In other implementations of the target communication device of the fourth aspect, the control circuit is used to perform the features of the implementation of the method according to the first aspect. Therefore, the implementation of the target communication device includes one or more features of the corresponding implementation of the method of the first aspect.

[0042] The target communication device of the fourth aspect achieves all the advantages and effects of the method of the first aspect.

[0043] In a fifth aspect, the present invention provides a source communication device for performing multipath communication. The source communication device comprises: a control circuit, the control circuit being used to provide a first group of data messages in a plurality of data messages to a target communication device via a first path and to provide a second group of data messages in a plurality of data messages to the target communication device via a second path, wherein a header of each data message comprises message information indicating an association between the plurality of data messages. The plurality of data messages comprises different data messages with different payloads or duplicate data messages with copies of the same payload.

[0044] In other implementations of the source communication device of the fifth aspect, the control circuit is used to perform the features of the implementation of the method according to the second aspect. Therefore, the implementation of the source communication device includes one or more features of the corresponding implementation of the method of the second aspect.

[0045] The source communication device of the fifth aspect achieves all the advantages and effects of the method of the second aspect.

[0046] In a sixth aspect, the present invention provides a network entity for performing multipath communication. The network entity includes an entity control circuit, and the entity control circuit is used to obtain a first group of data packets from a source communication device, wherein the header of each data packet in the first group of data packets includes message information, wherein the message information indicates the association between the first group of data packets. The entity control circuit is also used to map the uplink sequence number of each data packet in the received first group of data packets to a downlink sequence number according to the message information. The entity control circuit is also used to: according to the mapping of the uplink sequence number to the downlink sequence number, provide each received data packet in the first group of data packets including the message information to at least one of the target communication device or another network entity.

[0047] In other implementations of the network entity of the sixth aspect, the control circuit is used to perform the features of the implementation of the method according to the third aspect. Therefore, the implementation of the network entity includes one or more features of the corresponding implementation of the method of the second aspect.

[0048] The network entity of the sixth aspect realizes all the advantages and effects of the method of the third aspect.

[0049] In a seventh aspect, the present invention provides a computer program product comprising a non-transitory computer-readable storage medium storing computer-readable instructions, wherein the computer-readable instructions can be executed by a computerized device comprising processing hardware to perform the method described in the first, second or third aspect above.

[0050] The computer program product of the seventh aspect achieves all the advantages and effects of the method of the first aspect, the second aspect or the third aspect.

[0051] It should be noted that all devices, elements, circuits, units and modules described in this application can be implemented by software or hardware elements or any type of combination thereof. All steps performed by various entities described in this application and the described functions to be performed by various entities are intended to indicate that the corresponding entities are used to perform the corresponding steps and functions. Even in the description of the following specific embodiments, the specific functions or steps to be performed by the external entity are not reflected in the description of the specific detailed elements of the entity performing the specific steps or functions, the technician should be aware that these methods and functions can be implemented in the corresponding software or hardware elements, or in any combination of such elements. It should be understood that, without departing from the scope of the invention defined in the appended claims, various combinations of features of the present invention can be performed.

[0052] Additional aspects, advantages, features and objects of the present invention will become apparent from the accompanying drawings and detailed description of illustrative implementations interpreted in conjunction with the following appended claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] The above summary and the detailed description of the following illustrative embodiments may be better understood by reading in conjunction with the accompanying drawings. In order to illustrate the present invention, exemplary structures of the present invention are shown in the accompanying drawings. However, the present invention is not limited to the specific methods and tools disclosed herein. In addition, it should be understood by those skilled in the art that the accompanying drawings are not drawn to scale. Where possible, the same elements are represented by the same numbers.

[0054] Embodiments of the present invention will now be described, by way of example only, with reference to the following drawings, in which:

[0055] Figure 1 is a flow chart of a method for performing multipath communication at a target communication device provided by an embodiment of the present invention;

[0056] Figure 2 is a flow chart of a method for performing multipath communication at a source communication device provided by an embodiment of the present invention;

[0057] Figure 3 is a flow chart of a method for performing multipath communication at a network entity provided by an embodiment of the present invention;

[0058] Figure 4A is a network environment diagram of a system having a source communication device and a target communication device provided by an embodiment of the present invention;

[0059] Figure 4B is a diagram of data communication through a repetitive mode provided by an embodiment of the present invention;

[0060] Figure 4C is a diagram of data communication through a partitioning mode provided by an embodiment of the present invention;

[0061] Figure 4D is a block diagram of various exemplary components of a source communication device provided by an embodiment of the present invention;

[0062] Figure 4E is a block diagram of various exemplary components of a target communication device provided by an embodiment of the present invention;

[0063] Figure 5 is a network environment diagram of a system having various nodes of a cellular network provided by an embodiment of the present invention;

[0064] Figure 6 is a block diagram of various exemplary components of a network entity provided by an embodiment of the present invention;

[0065] Figure 7 is a diagram of an exemplary scenario for multipath communication with a network layer provided by an embodiment of the present invention;

[0066] Figure 8 is a diagram of an exemplary scenario for performing multipath communication through different wireless access technologies provided by an embodiment of the present invention;

[0067] Fig. 9 is a diagram of an exemplary scenario for performing multipath communication using message repetition and division at a packet data convergence protocol (PDCP) layer according to an embodiment of the present invention;

[0068] Fig.10 is a diagram of an exemplary structure of a general packet radio service (GPRS) tunneling protocol user plane (GTP-U) header provided by an embodiment of the present invention;

[0069] Fig.11 It is a timing diagram of a part of a protocol data unit (PDU) session establishment process provided by an embodiment of the present invention;

[0070] Fig.12 is a diagram of an exemplary indicator in a header of a data message provided by an embodiment of the present invention;

[0071] Fig.13is a diagram describing an exemplary scenario of vehicle-to-vehicle (V2V) multi-path communication provided by an embodiment of the present invention.

[0072] In the drawings, an underlined number is used to indicate the item in which the underlined number is located or an item adjacent to the underlined number. A non-underlined number refers to the item identified by the line connecting the non-underlined number to the item. When a number is not underlined and has an associated arrow, the non-underlined number is used to identify the general item to which the arrow points. DETAILED DESCRIPTION

[0073] The following detailed description describes embodiments of the invention and ways in which these embodiments may be implemented. Although some modes of implementing the invention have been disclosed, those skilled in the art will recognize that there may be other embodiments for implementing or practicing the invention.

[0074] Figure 1 1 is a flow chart of a method 100 for performing multipath communication at a target communication device provided by an embodiment of the present invention. The method 100 comprises, for example, Figure 4A The method 100 includes steps 102 and 104.

[0075] In step 102, multiple data messages are obtained from a source communication device via two or more different paths. When using at least one radio access technology, communication protocol, radio link, interface or a combination thereof, each of the two or more different paths is different from the other paths. In one example, the two or more different paths may refer to a cellular communication path and a sidelink communication path. In another example, the two or more different paths may refer to different device-to-device communications. The header of each data message in the multiple data messages includes message information. The message information indicates the association between the multiple data messages. Alternatively, the message information links the multiple data messages, regardless of which radio access technology, communication protocol or radio link is used by the two or more different paths. The message information in each data message of the source communication device is the same as the message information in each data message of the target communication device, regardless of which radio access technology, communication protocol or radio link is used by the two or more different paths. The multiple data messages include different data messages with different loads or duplicate data messages with the same load copy.

[0076] In step 104, a first group of data messages among the plurality of data messages received through the first path and a second group of data messages among the plurality of data messages received through the second path are identified according to the message information. In one example, the message information may be a message identifier (e.g., for a divided data message or a duplicate data message) or a sequence number stored (i.e., retained) in a header of each data message among the plurality of data messages, regardless of which path the plurality of data messages travel from the source communication device to the target communication device. Such message information is used to identify which data messages are received from which path among two or more different paths at the target communication device.

[0077] According to an embodiment, one of the first path or the second path corresponds to device-to-device communication between a source communication device and a target communication device. Alternatively, the first path of two or more different paths is a cellular communication path, and the second path of the two or more different paths is a sidelink communication path corresponding to device-to-device communication. It should be noted that the cellular communication path has different transmission characteristics from the sidelink communication path. For example, the cellular communication path provides a better signal coverage area than the sidelink communication path, and the sidelink communication path reduces latency, improves capacity and network performance through spatial frequency reuse. It is well known that next-generation services, such as vehicle-to-everything (V2X) services, have stringent quality of service (QoS) requirements specified in the 3rd generation partnership project (3GPP). Therefore, two or more different paths can be used for data communication simultaneously in order to achieve the target QoS requirements. For example, in Figure 4A Other examples of the first path and the second path are described in .

[0078] According to an embodiment, method 100 also includes the target communication device filtering duplicate data packets from multiple data packets received at the target communication device according to the message information. In the case where the multiple data packets obtained by the target communication device include duplicate data packets, the redundant data packets in the first group of data packets or the second group of data packets are removed before finally presenting (i.e., outputting to the user for consumption) on the target communication device. In one example, filtering of duplicate data packets is performed at a specific network layer (also referred to as a protocol layer) of a wireless protocol stack in the target communication device, such as an application layer, a convergence layer (in the case of a vehicle, a V2X layer), or a packet data convergence protocol (PDCP) layer.

[0079] According to an embodiment, the method 100 further includes: the target communication device reorders the multiple data packets according to the sequence number associated with each of the multiple data packets according to the message information, wherein, in the partitioning mode, the multiple data packets include different data packets obtained through the first path and the second path. In the case where the multiple data packets obtained by the target communication device include different data packets, the message information including the dedicated sequence number is checked in each data packet, and accordingly, the multiple data packets are aligned in sequence before being finally presented (i.e., output to the user for consumption) on the target communication device. The first group of data packets received through the first path and the second group of data packets received simultaneously through the second path improve the data throughput and reduce the delay of data communication.

[0080] Steps 102 and 104 are merely illustrative, and other alternatives may be provided in which one or more steps are added, one or more steps are deleted, or one or more steps are provided in a different order without departing from the scope of the claims herein.

[0081] Figure 2 2 is a flow chart of a method 200 for performing multipath communication at a source communication device provided by an embodiment of the present invention. The method 200 comprises, for example, Figure 4A The source communication device described in is executed.

[0082] In step 202, a first group of data messages in a plurality of data messages are provided to a target communication device via a first path and a second group of data messages in a plurality of data messages are provided to the target communication device via a second path. Alternatively, multipath communication is performed at a source communication device to provide a plurality of data messages to the target communication device. Multipath communication refers to sending data to a common destination device (e.g., a target communication device in this case) via two or more different paths, wherein each path is different from other paths when data is sent using at least one wireless access technology, communication protocol, wireless link, interface, or a combination thereof. For example, a data item (e.g., text, audio, video, or other media, or a combination thereof) can be sent from a source communication device to a target communication device. Such a data item is segmented into a plurality of data messages. The header of each data message in a plurality of data messages includes message information indicating association between the plurality of data messages. For example, the message information indicates that the plurality of data messages belong to the same data item, and further indicates whether the data message is a duplicate data message or a partitioned data message. Alternatively, the message information links the multiple data messages, regardless of the different wireless access technologies, communication protocols, or wireless links that the first group of data messages and the second group of data messages travel from the source communication device to the target communication device. The multiple data messages include different data messages with different payloads (i.e., divided data messages) or duplicate data messages with the same payload copy. For example, in Figure 4Band Figure 4C Repeating data messages and dividing data messages are further described in detail in FIG.

[0083] According to an embodiment, at least one of the first path or the second path corresponds to a device-to-device communication between a source communication device and a target communication device. For example, the first path may be a cellular communication path, and the second path may be a sidelink communication path corresponding to the device-to-device communication. In the case where the first path is a cellular communication path, a first group of data messages of a plurality of data messages communicates via a cellular interface (e.g., a Uu interface). In the case where the second path is a sidelink communication path, a second group of data messages of a plurality of data messages communicates via a sidelink interface (e.g., a PC5 or PC3 interface) or other interfaces for device-to-device communication. The source communication device may support a cellular interface and a sidelink interface. Alternatively, the first path and the second path may refer to different device-to-device communications, for example, IEEE 802.11p (also known as dedicated short-range communication (DSRC) or intelligent transport system (ITS) dedicated to road transportation informatization-G5), wireless fidelity (Wi-Fi), Wi-Fi Direct, long term evolution (LTE) Direct, device-to-device communication based on 5G new radio (NR), etc.

[0084] According to an embodiment, method 200 also includes selecting a repetition mode or a partitioning mode by a source communication device to send a plurality of data messages to a target communication device through two or more different paths. The repetition mode or the partitioning mode is selected before the data session starts or during the data session. Optionally, one of the repetition mode or the partitioning mode is set as a default at the source communication device. Optionally, the selection of the repetition mode or the partitioning mode is based on a user input provided to the source communication device. Alternatively, the selection is automatically performed according to the type or size of the data (or data item) to be sent. In the repetition mode, repeated data messages with the same load copy communicate through at least two different paths to ensure that all data messages reliably reach a common destination device, such as a target communication device. The repetition mode realizes the redundancy of the wireless link, thereby improving the reliability of data communication. In the partitioning mode, a plurality of data messages are divided into a first group of data messages and a second group of data messages, wherein each data message has a different load. Thereafter, the first group of data messages and the second group of data messages are provided from the source communication device to a common destination device, such as a target communication device, through at least two different paths to improve throughput and reduce delay.

[0085] According to an embodiment, the method 200 further includes: the source communication device sends the first group of data packets to the network entity through the first path in the uplink transmission, and sends the second group of data packets to the target communication device through the second path according to the selected repetition mode as repeated data packets. In this case, in the repetition mode, the load of the first group of data packets is at least the same as the load of the second group of data packets. Optionally, the method 200 further includes: the source communication device sends the first group of data packets to the network entity through the first path in the uplink transmission, and sends the second group of data packets to the target communication device through the second path. In this case, in the split mode, the load of the first group of data packets is different from the load of the second group of data packets. In the case where the first path is a cellular communication path, in the uplink transmission, the first group of data packets is sent to the network entity, such as a base station. Optionally, the first group of data packets passes through various network entities, such as a source radio access network node (e.g., a base station), a core network entity, or a target radio access network node, where different types of communication protocols are used. In other words, different headers and identifiers can be used from one node to another network node. Compared with conventional methods and systems, the message information in the header of each data message in a plurality of data messages is additional control information that remains unchanged in the header of each data message, regardless of which wireless access technology, communication protocol or wireless link is used by the first path and the second path and which network node the first group of data messages passes through.

[0086] According to an embodiment, a header of each data packet in a plurality of data packets or a signaling message sent by a source communication device to at least one of a network entity or a target communication device when a data session is established or updated includes an indicator. The indicator indicates that a multipath function is enabled at the network entity or at the target communication device. The signaling message may refer to control plane signaling or other signaling messages. In one example, the indicator may be a specific bit value (e.g., bit value "1") in a binary bit value ("0" or "1") that may be set at the source communication device in at least one reserved field in a data packet of a specific network layer (e.g., a PDCP layer header). The specific bit value acts as a flag to signal to the network entity or the target communication device that the multipath function will be enabled. Fig.12 Examples of indicators are further described in . Enabling multipath functionality refers to an indication that specific processing needs to be provided to a data message having the indicator. Specific processing refers to a configuration change or network capability that enables storing (or retaining) message information in a header of each of a plurality of data messages received at a network entity (e.g., a base station) and multiplexing the message information to further provide each received message to a target communication device.

[0087] Step 202 is merely illustrative, and other alternatives may be provided in which one or more steps are added, one or more steps are deleted, or one or more steps are provided in a different order without departing from the scope of the claims herein.

[0088] Figure 3 is a flow chart of a method 300 for performing multipath communication at a network entity provided by an embodiment of the present invention. The method 300 comprises, for example, Figure 6 The method 300 includes steps 302 and 306.

[0089] In step 302, a first group of data messages is obtained from a source communication device. For example, the first group of data messages is obtained through a cellular communication path. The header of each data message in the first group of data messages includes message information. The message information indicates the association between the first group of data messages.

[0090] In step 304, the uplink sequence number of each data message in the received first group of data messages is mapped to the downlink sequence number according to the message information. According to an embodiment, the uplink sequence number is received from the source communication device in a specified network layer. The uplink sequence number is mapped to the downlink sequence number in the specified network layer. The specified network layer is at least one of a PDCP layer, a service data adaptation protocol (SDAP) layer, or another network layer. In one example, a network entity (e.g., a source network access node) can be used to perform mapping of uplink PDCP sequence numbers to downlink PDCP sequence numbers in order to resolve incorrect sorting of data messages and enable a target communication device to compare (or match) data messages received through a sidelink communication path with data messages received through a cellular communication path. Therefore, in this case, the network entity (or target network entity) does not need to apply a traditional PDCP sequence derivation method to the downlink data message.

[0091] In step 306, each received data packet including the packet information in the first group of data packets is provided to at least one of a target communication device or another network entity according to the mapping of the uplink sequence number to the downlink sequence number.

[0092] Optionally, method 300 also includes: the network entity attaches the uplink sequence number (SN) received from the source communication device to the core network protocol-based header of each received data packet in the first group of data packets. The method also includes: the network entity sends each received data packet in the first group of data packets to the core network entity, and each received data packet in the first group of data packets has a core network protocol-based header including the attached uplink SN. The core network protocol-based header including the attached uplink SN is a modified core network protocol-based header including the attached uplink SN, as an extension of the header structure of the core network protocol-based header. Optionally, the core network protocol-based header is a general packet radio service (GPRS) tunneling protocol user plane (GTP-U) header. For example, in Fig.10 An example of a GTP-U header is described in . Alternatively, the first group of data packets may not be forwarded to the core network entity, but may be sent directly from the network entity to the target communication device in the downlink transmission. Optionally, the first group of data packets may not be forwarded to the core network entity, but may be forwarded to another network entity, such as a target wireless access node, and then the other network entity forwards the first group of data packets to the target communication device in the downlink transmission. In this case, the header based on the core network protocol may not be used.

[0093] According to an embodiment, the method 300 further includes: before downlink transmission of the received data packets in the first group of data packets to the target communication device, the network entity sets the uplink SN retrieved in each received data packet in the plurality of data packets as the downlink SN.

[0094] According to an embodiment, the method 300 further comprises: the network entity enabling the multipath function according to an indicator in the header of each data packet in the first group of data packets or in a signaling message sent by the source communication device. Fig.12 Examples of indicators in the header of a data message are described in Fig.11 An example of one or more signaling messages in a session is described in . Enabling multipath functionality includes storing (or retaining) message information in each data message in a first set of data messages received at a network entity, and multiplexing the message information to further provide each received message to a target communication device. Alternatively, enabling multipath functionality includes routing each data message in a first set of data messages having message information to another network entity, the network entity multiplexing the message information to further provide each received message to a target communication device via the network entity or another network entity.

[0095] Steps 302, 304, and 306 are merely illustrative, and other alternatives may be provided in which one or more steps are added, one or more steps are deleted, or one or more steps are provided in a different order without departing from the scope of the claims herein.

[0096] Figure 4A FIG. 4 is a block diagram of a network environment of a system 400A for performing multi-path communication provided by an embodiment of the present invention. Figure 4A , shows a network environment of a system 400A including a source communication device 402 and a target communication device 404. Also shown is a first path 406 and a second path 408. The source communication device 402 and the target communication device 404 can be used to establish communication with each other through two or more different paths (e.g., the first path 406 and the second path 408).

[0097] Each of the source communication device 402 and the target communication device 404 may include appropriate logic, circuits, interfaces and / or codes for data communication (sending / receiving data) through two or more different paths. According to an embodiment, each of the source communication device 402 and the target communication device 404 is at least one of the following: a vehicle, an electronic device used in a vehicle (e.g., an electronic control unit (ECU), an in-vehicle infotainment (IVI) system or other vehicle-mounted device), or a portable electronic device (e.g., a smartphone, a drone, an Internet of Things (IoT) device, a machine type communication (MTC) device, a handheld computing device, an evolved universal mobile telecommunications system (UMTS) terrestrial radio access (Evolved UMTSterrestrial radio access, E-UTRAN) NR dual connectivity (E-UTRA-NR dual connectivity, EN-DC) device or any other custom hardware for wireless telecommunications). The vehicle may be a non-autonomous driving vehicle, a semi-autonomous driving vehicle or an autonomous driving vehicle.

[0098] Multipath communication refers to sending data to a common destination device via two or more different paths, wherein each path is different from the other paths when sending data using at least one wireless access technology, communication protocol, wireless link, interface, or a combination thereof. Thus, the first path 406 is different from the second path 408 when sending data using wireless access technology, one or more communication protocols, wireless links, and / or interfaces.

[0099] In one example, the first path 406 may be a cellular communication path (i.e., communication based on a cellular network), and the second path 408 may be a sidelink communication path (i.e., device-to-device communication). Examples of communication based on a cellular network include, but are not limited to, fifth generation (5G) th The source communication device 402 or the target communication device 404 is a vehicle or an electronic device used in a vehicle, and the communication based on the cellular network can be a vehicle-to-network (V2N) communication, which is operated, for example, by using a Uu interface in a mobile broadband spectrum. The Uu interface refers to a wireless interface between a communication device and a wireless access network. In this example, a first path 406 uses a cellular network with different wireless access technologies, communication protocols, wireless links, and interfaces (e.g., a Uu interface) to send data, while a second path 408 uses a device-to-device communication independent of the cellular network. Device-to-device communication improves spectrum utilization and capacity, and improves network performance and throughput. Examples of device-to-device communication include, but are not limited to, IEEE802.11p, wireless fidelity (Wi-Fi), Wi-Fi Direct, LTE Direct, in-band device-to-device communication, out-of-band device-to-device communication, or device-to-device communication based on proximity services (ProSe). Device-to-device communication can be performed in a cellular system, which is called in-band device-to-device communication, or can be performed in an unlicensed spectrum, which is called out-of-band device-to-device communication. Device-to-device communication is direct communication between a source communication device 402 and a target communication device 404, which can be implemented through different interfaces (e.g., a PC5 interface, a PC3 interface, or other interfaces based on a wireless local area network (WLAN)).

[0100] In another example, the first path 406 may use IEEE 802.11p, and the second path 408 may use 5G-V2X communication or LTE-V2X (via PC5) communication. In yet another example, the first path 406 and the second path 408 may use different device-to-device communications, for example, the first path 406 may use LTE PC5, and the second path 408 may use NR PC5. In yet another example, the first path 406 may use Wi-Fi-based communication, and the second path 408 may use device-to-device communication based on a PC5 interface.

[0101] In operation, a user of the source communication device 402 may wish to communicate data with the target communication device 404. According to an embodiment, the source communication device 402 is configured to select a repetition mode or a partitioning mode to send multiple data packets to the target communication device 404 through two or more different paths. The repetition mode or the partitioning mode is selected before the data session begins or during the data session. For example, Figure 4B and Figure 4C The repetition pattern and the partitioning pattern are described in detail respectively.

[0102] The source communication device 402 is further configured to provide a first group of data packets in the plurality of data packets to the target communication device 404 via a first path 406 and provide a second group of data packets in the plurality of data packets to the target communication device 404 via a second path 408. The plurality of data packets include different data packets with different payloads (e.g., when a partitioning mode is selected) or duplicate data packets with the same payload copy (e.g., when a repeating mode is selected). The header of each data packet includes message information indicating association between the plurality of data packets.

[0103] Optionally, the source communication device 402 is used to provide a second set of data packets to the target communication device 404 via a second path 408 in a multi-hop process. For example, even if the target communication device 404 moves from the source communication device 402 to outside the specified device-to-device communication range, the first set of data packets can pass through multiple communication devices in the device-to-device communication, thereby finally reaching the destination device, such as the target communication device 404. For example, the source communication device 102 is "A" and the target communication device is "D". "B" and "C" are intermediate communication devices. "B" can be within the device-to-device communication range between "A" and "C" but not "D". "C" can be within the device-to-device communication range between "B" and "D" but not "C". Therefore, in this case, "A" can provide the second set of data packets to "D" in the following manner: A to B to C to D, and due to the large cellular communication coverage, "D" can obtain the first set of data packets through the cellular communication path in the downlink transmission.

[0104] The target communication device 404 is used to obtain multiple data messages from the source communication device 402 through two or more different paths. It should be noted that the header of each data message in the multiple data messages includes message information. The message information indicates the association between the multiple data messages. The message information in each data message of the source communication device 402 is the same as the message information in each data message of the target communication device 404, regardless of which radio access technology, communication protocol or wireless link is used by the two or more different paths. The multiple data messages include different data messages with different loads or duplicate data messages with the same load copy. The target communication device 404 is also used to identify a first group of data messages in the multiple data messages received through the first path 406 and a second group of data messages in the multiple data messages received through the second path 408 according to the message information.

[0105] Figure 4B FIG. 1 is a block diagram of performing data communication through a repetitive mode provided by an embodiment of the present invention. Figure 4A Component Description Figure 4B . refer to Figure 4B , an exemplary scenario 400B describing data communication in a repeating mode is shown. Also shown are a source communication device 402, a target communication device 404, a first path 406, a second path 408, a first set of data packets 410a, 412a, and 414a, and a second set of data packets 410b, 412b, and 414b.

[0106] There are two modes (or options) for multipath communication. These two modes are called repetition mode and partitioning mode. Repetition mode implements redundancy of wireless links, thereby improving the reliability of data communication. In repetition mode, duplicate data packets with the same payload copies are communicated through at least two different paths to ensure that all data packets arrive at a common destination device, such as the target communication device 404. In partitioning mode, different data packets with different payloads are provided to a common destination device, such as the target communication device 404, through at least two different paths at the same time to improve throughput and reduce delay. In other words, some of the multiple data packets are communicated through one path, while other data packets are communicated simultaneously through another path to improve throughput and reduce delay.

[0107] According to an embodiment, the source communication device 402 is used to select a repetition mode to send multiple data messages to the target communication device 404 through two or more different paths. The repetition mode is selected before the data session begins, that is, before the transmission of the data message begins, or during the data session. According to the selected repetition mode, the source communication device 402 is used to provide a first group of data messages 410a, 412a and 414a through a first path 406. The source communication device 402 is also used to provide a second group of data messages 410b, 412b and 414b to the target communication device 404 through a second path 408 according to the selected repetition mode, as repeated data messages. In this case, in the repetition mode, the load of the first group of data messages 410a, 412a and 414a is at least the same as the load of the second group of data messages 410b, 412b and 414b. The data messages of the first group of data messages 410a, 412a and 414a and the duplicate data messages of the first group of data messages 410a, 412a and 414a (i.e., the second group of data messages 410b, 412b and 414b) are transmitted in sequence (at Figure 4B are also represented by the consecutive numbers 1, 2 and 3 in the text).

[0108] In an exemplary implementation, the target communication device 404 is used to filter duplicate data packets from multiple data packets received at the target communication device 404 according to the packet information. Therefore, in order to ensure that the data is error-free, redundant data packets in the first group of data packets 410a, 412a and 414a and the second group of data packets 410b, 412b and 414b that may be obtained by the target communication device 404 are filtered out. This multi-path communication performed in a repetitive mode is conducive to achieving better reliability than communication performed through a single path.

[0109] Figure 4C FIG. 1 is a block diagram of performing data communication through a partitioning mode provided by an embodiment of the present invention. Figure 4A and Figure 4B Component Description Figure 4C . refer to Figure 4C , an exemplary scenario 400C is shown describing data communication in a split mode. In the split mode, a plurality of data packets are split into a first group of data packets 416, 420, and 424 communicated via a first path 406 and a second group of data packets 418, 422, and 426 communicated via a second path 408. In the split mode, the payload of the first group of data packets 416, 420, and 424 is different from the payload of the second group of data packets 418, 422, and 426. In an example, as Figure 4CAs shown, if a total of six data packets 416, 418, 420, 422, 424, and 426 are to be provided to the target communication device 404, the plurality of data packets are divided and communicated simultaneously through two paths (i.e., the first path 406 and the second path 408) to improve throughput and reduce delay. The transmission order of the data packets is also represented by consecutive numbers 1, 2, 3, 4, 5, and 6. The selection of the repetition mode or the division mode can be made by the source communication device 402 to improve the QoS of the communication between the source communication device 402 and the target communication device 404.

[0110] Figure 4D is a block diagram of various exemplary components of a source communication device provided by an embodiment of the present invention. Figure 4A , Figure 4B and Figure 4C Component Description Figure 4D . refer to Figure 4D , a source communication device 402 is shown. The source communication device 402 includes a control circuit 428, a transceiver 430, one or more interfaces 432, an input / output (I / O) device 434, and a memory 436. The control circuit 428 can be communicatively coupled to the transceiver 430, the one or more interfaces 432, the I / O device 434, and the memory 436. In the case where the source communication device 402 is a vehicle, the control circuit 428 is communicatively coupled to various components of the source communication device 402 via an in-vehicle network, such as an in-vehicle data bus, such as a vehicle area network (VAN) and / or a controller area network (CAN) bus.

[0111] As described above, in this embodiment and in the following embodiments, the control circuit may be a general purpose processor running dedicated software or a dedicated hardware circuit.

[0112] The control circuit 428 is used to provide multiple data packets to the target communication device 404 through two or more different paths. In one implementation, the control circuit 428 is used to execute instructions stored in the memory 436. Examples of the control circuit 428 may include, but are not limited to, a microprocessor, a microcontroller, a complex instruction set computing (CISC) processor, an application-specific integrated circuit (ASIC) processor, a reduced instruction set (RISC) processor, a very long instruction word (VLIW) processor, a central processing unit (CPU), a state machine, a data processing unit, and other processors or circuits. In addition, the control circuit 428 may refer to one or more separate processors, processing devices, or processing units as part of a machine.

[0113] The transceiver 430 may include appropriate logic, circuitry, and / or interfaces that may be used to communicate with one or more external devices (e.g., a wireless access network node (e.g., a base station) or a target communication device 404) via two or more different paths. Examples of the transceiver 430 may include, but are not limited to, an antenna, a telematics unit, a radio frequency (RF) transceiver, one or more amplifiers, one or more oscillators, a digital signal processor, a coder-decoder (CODEC) chipset, and / or a subscriber identity module (SIM) card. The transceiver 430 may communicate wirelessly (e.g., by using various communication protocols of the first path 406 and the second path 408) Figure 4A (described in ).

[0114] One or more interfaces 432 refer to a sidelink interface and a cellular interface. Examples of sidelink interfaces include, but are not limited to, a PC5 interface, a PC3 interface, or another interface that supports device-to-device communication. Examples of cellular interfaces include, but are not limited to, a Uu interface. In an exemplary implementation, a unified interface may be provided that enables communication with two or more paths through the same unified interface.

[0115] I / O device 434 refers to an input and output device that can receive input from a user and provide output to a user. I / O device 434 can be communicatively coupled to control circuit 428. Examples of input devices may include, but are not limited to, a touch screen, such as a touch screen of a display device, a microphone, a motion sensor, a light sensor, a dedicated hardware input unit (e.g., a button), and a docking station. Examples of output devices include display devices and speakers. Examples of display devices include, but are not limited to, vehicle displays (e.g., a head-up display (HUD), an augmented reality system (AR-HUD), a display screen of a driver information console (DIC), an infotainment unit or a head unit (HU)) and non-vehicle displays (e.g., a smart glass display, a display screen of a portable device, or other display screens).

[0116] The memory 436 may include suitable logic, circuitry, and / or interfaces that may be used to store machine code and / or instructions having at least one code segment executable by the control circuit 428. The memory 436 may store a plurality of data packets for processing and presentation to the application layer of the source communication device 402. Implementation examples of the memory 436 may include, but are not limited to, electrically erasable programmable read-only memory (EEPROM), random access memory (RAM), read only memory (ROM), hard disk drive (HDD), flash memory, secure digital (SD) card, solid-state drive (SSD), and / or CPU cache memory. The memory 436 may store an operating system and / or other program products to operate the source communication device 402. Computer-readable storage media for providing non-transitory memory may include, but are not limited to, electronic storage devices, magnetic storage devices, optical storage devices, electromagnetic storage devices, semiconductor storage devices, or any suitable combination thereof.

[0117] Figure 4E is a block diagram of various exemplary components of a target communication device provided by an embodiment of the present invention. Figures 1 to 3 and FIG. 4A to FIG. 4D Component Description Figure 4E . refer to Figure 4E, a target communication device 404 is shown. The target communication device 404 includes a control circuit 438, a transceiver 440, one or more interfaces 442, an input / output (I / O) device 444, and a memory 446. The control circuit 438 can be communicatively coupled to the transceiver 440, the one or more interfaces 442, the I / O device 444, and the memory 446. In the case where the target communication device 404 is a vehicle, the control circuit 438 is communicatively coupled to various components of the target communication device 404 through an in-vehicle network, such as an in-vehicle data bus, such as a vehicle area network (VAN) and / or a controller area network (CAN) bus.

[0118] The control circuit 438 is used to obtain multiple data packets through two or more different paths. In one implementation, the control circuit 428 is used to execute instructions stored in the memory 436. An example of the control circuit 438 is similar to the control circuit 428 ( Figure 4D ). Similarly, implementation examples of the transceiver 440, the one or more interfaces 442, the I / O device 444, and the memory 446 are similar to Figure 4D An implementation example of a transceiver 430, one or more interfaces 432, an I / O device 434, and a memory 436.

[0119] Figure 5 FIG. 5 is a block diagram of a network environment of a system 500 having various nodes of a cellular network provided by an embodiment of the present invention. Figures 1 to 3 and FIG. 4A to FIG. 4E Component Description Figure 5 . refer to Figure 5 , shows a system 500, which includes a source communication device 402, a target communication device 404 and one or more network entities of a cellular network 502, such as a source radio access network (RAN) node 504, a core network entity 506, and a target RAN node 508.

[0120] Each of the source RAN node 504 and the target RAN node 508 refers to a wireless base station, such as a NodeB, an evolved Node B (eNB), a Next Generation Node B (gNB), a base transceiver station, an access point base station, a base station router, or any other network entity capable of communicating with a wireless device (e.g., the source communication device 402 or the target communication device 404). The cellular network 502 covers a geographic area divided into cell areas, where one or more cell areas are served by the source RAN node 504 and the target RAN node 508.

[0121] The core network entity 506 is part of the cellular network 502 that connects different nodes (or parts) of the access network (i.e., RAN). In LTE, the core network entity 506 includes, for example, a serving gateway (S-GW), a packet data network (PDN) gateway (PDN GW), a mobility management entity, a home subscriber server (HSS), as an evolved packet core (EPC). In the case of 5G, network entities are referred to as "functions" and are not usually referred to as "nodes". For example, the functions of 4GS-GW and PDN-GW are merged into a single entity, called a user plane function (UPF). In another example, a 4G MME is divided into two separate functions, such as an access management function (AMF) and a session management function (SMF). However, in the present invention, a network entity may cover both an access node entity and a core network entity (e.g., a network node or function).

[0122] In operation, the source communication device 402 is configured to provide a first group of data packets among a plurality of data packets to a target communication device 404 via a cellular communication path 510. In order to provide the first group of data packets to the target communication device 404 via the cellular communication path 510, the first group of data packets is first sent to a network entity (e.g., a source RAN node 504) in an uplink transmission 512. Thereafter, the first group of data packets may be further sent to the target communication device 404 or another network entity, such as a core network entity 506 and a target RAN node 508, to be provided to the target communication device 404 in a downlink transmission 514. The source communication device 402 is further configured to send a second group of data packets among the plurality of data packets to the target communication device 404 via a sidelink communication path 516. The header of each data packet includes message information indicating an association between the plurality of data packets.

[0123] The network entity (eg, the source RAN node 504) is configured to obtain a first set of data packets from the source communication device 402. A header of each data packet in the first set of data packets includes packet information.

[0124] According to an embodiment, the network (e.g., the source RAN node 504) is configured to enable a multipath function according to an indicator in a header of each data packet in the first set of data packets or in a signaling message sent by the source communication device 402. The multipath function refers to a network capability that enables storing (or retaining) packet information in a header of each data packet in the first set of data packets received at a network entity (e.g., the source RAN node 504), and multiplexing the packet information to further provide each received packet to the target communication device 404. In the case where data packets from a network entity (e.g., source RAN node 504) pass through a core network entity 506 or one or more other RAN nodes (e.g., target RAN node 508), a multipath function refers to a network capability that enables routing of each data packet in a first group of data packets having packet information to another network entity, which multiplexes the packet information to further provide each received packet to a target communication device 404 via another network entity (e.g., target RAN node 508) through the network entity (e.g., source RAN node 504).

[0125] The network entity (e.g., source RAN node 504) is further configured to map, according to the message information, an uplink sequence number (e.g., uplink PDCP sequence number) of each data packet in the received first group of data packets to a downlink sequence number (e.g., downlink PDCP sequence number). The network entity (e.g., source RAN node 504) is further configured to provide, according to the mapping of the uplink sequence number to the downlink sequence number, each received data packet in the first group of data packets including the message information to at least one of the target communication device 404 or another network entity (e.g., core network entity 506 or target RAN node 508).

[0126] The target communication device 404 is used to obtain multiple data messages through the cellular communication path 510 and the sidelink communication path 516. The multiple data messages include different data messages with different payloads or duplicate data messages with the same payload copy. The target communication device 404 is used to identify a first group of data messages among the multiple data messages received through the cellular communication path 510 and a second group of data messages among the multiple data messages received through the sidelink communication path 516 according to the message information.

[0127] Figure 6 FIG. 1 is a block diagram of various exemplary components of a network entity provided by an embodiment of the present invention. FIG. 4A to FIG. 4E and Figure 5 Component Description Figure 6 . refer to Figure 6 , shows a network entity 600. The network entity 600 corresponds to one of the network entities of the cellular network 502 ( Figure 5). The network entity 600 covers both the access network entity (e.g., RAN node) and the core network entity (e.g., node or function). The network entity 600 includes an entity control circuit 602, a transceiver 604, and a memory 606. The entity control circuit 602 is communicatively coupled to the transceiver 604 and the memory 606.

[0128] The entity control circuit 602 is used to obtain a first group of data packets from the source communication device 402, wherein the header of each data packet in the first group of data packets includes message information. The message information indicates the association between the first group of data packets. The example of the entity control circuit 602 is similar to the control circuit 428 ( Figure 4D ). As described above, in this embodiment and in the following embodiments, the physical control circuit or simply the control circuit may be a general purpose processor running dedicated software or a dedicated hardware circuit. Similarly, the implementation examples of the transceiver 604 and the memory 606 are similar to Figure 4D An implementation example of the transceiver 430 and the memory 436 is shown.

[0129] According to an embodiment, the entity control circuit 602 is used to attach an uplink sequence number (SN) received from the source communication device 402 to a header based on the core network protocol of each received data message in the first group of data messages. The entity control circuit 602 is also used to send each received data message in the first group of data messages to the core network entity 506, and each received data message in the first group of data messages has a header based on the core network protocol including the attached uplink SN. The header based on the core network protocol including the attached uplink SN is a modified header based on the core network protocol including the attached uplink SN, as an extension of the header structure of the header based on the core network protocol. Optionally, the header based on the core network protocol is a GTP-U header. The entity control circuit 602 is also used to set the retrieved uplink SN in each received data message in the multiple data messages as a downlink SN before the data message received in the first group of data messages is transmitted downlink to the target communication device 404.

[0130] According to an embodiment, the entity control circuit 602 is used to enable the multipath function according to an indicator in a header of each data packet in the first group of data packets or in a signaling message sent by the source communication device 402. Enabling the multipath function includes storing the message information in each data packet in the first group of data packets received by the network entity 600, and multiplexing the message information to further provide each received message to the target communication device 404. Enabling the multipath function also includes routing each data packet in the first group of data packets with the message information to another network entity (e.g., the core network entity 506), which multiplexes the message information to further provide each received message to the target communication device 404 through the network entity 600 or another network entity.

[0131] Figure 7 FIG. 7 shows an exemplary scenario 700 of multipath communication with a network layer provided by an embodiment of the present invention. FIG. 4A to FIG. 4E and Figure 5 , Figure 6 Component Description Figure 7 . refer to Figure 7 , shows a first group of network layers 702A (i.e., user plane protocol stack) in the source communication device 402 and a second group of network layers 702B (i.e., corresponding user plane protocol stack) in the target communication device 404. Each of the first group of network layers 702A and the second group of network layers 702B includes a physical layer (physical layer, PHY), a media access control (media access control, MAC) layer, a radio link control (radio link control, RLC) layer, a PDCP layer, a convergence layer, and an application layer. In some embodiments, for example, in the case of a cellular network supporting 5G (i.e., an NR user plane protocol stack), a service data adaptation protocol (service data adaptation protocol, SDAP) layer is additionally provided in the source communication device 402 and the target communication device 404. Each network layer may also be referred to as a protocol layer of the user plane protocol stack.

[0132] According to an embodiment, methods for performing multipath communication at the source communication device 402, the network entity 600, and the target communication device 404 may be implemented at different network layers. Depending on the specific network layer (or protocol layer) at which data duplication or partitioning is performed in the source communication device 402 (and therefore in the target communication device 404), different methods (or schemes) may be used to perform multipath communication. The different methods include communication device-based methods and network-based methods.

[0133] In the communication device-based method, the source communication device 402 is used to generate a message identifier (e.g., for repeated or divided messages) or a sequence number. The message identifier (or sequence number) is attached to the header of each data message in the multiple data messages to be provided to the target communication device 404 (e.g., at the application layer or the convergence layer (e.g., the V2X layer in the case of a vehicle)). Optionally, the message identifier (or sequence number) is introduced into the header of each data message of the communication layer, the application layer, or the V2X layer (in the case of a vehicle) to reduce the impact on the existing protocol layers of the user plane protocol stack.

[0134] Typically, before each data message is passed to the next layer (i.e., the RLC layer), the transmitting end (i.e., the source communication device 402) in the PDCP layer assigns a sequence number to each data message. The sequence number is used at the receiving end (i.e., the target communication device 404) of the PDCP layer to align the data messages in sequence. However, currently, there are problems when transmitting data messages using different paths (e.g., the cellular communication path 510 and the sidelink communication path 516) of different interfaces (e.g., the NR Uu interface and the NR PC5 interface). The problem is that the target communication device 404 may not be able to compare (or match) the data message received through the cellular interface (i.e., the Uu interface) with the data message received from the sidelink interface (i.e., the PC5 interface). In this case, the downlink sequence number and the uplink sequence number of the data message may be different, or the message may become out of order (i.e., the order is incorrect). Therefore, in conventional methods and systems, it is impossible to compare the data message sent through the sidelink interface with the data message sent through the cellular interface. Therefore, in the present invention, message information (i.e., a message identifier or a dedicated sequence number used to divide data messages or duplicate data messages) is attached (or assigned) to the header of each data message in the upper layer (i.e., the application layer or the convergence layer (e.g., the V2X layer in the case of a vehicle)). This message information is additional control information (e.g., an additional message identifier or an additional sequence number in addition to the usual PDCP sequence number), which is retained in the header of each data message in a plurality of data messages, regardless of which path (e.g., the cellular communication path 510 and the sidelink communication path 516) or network node the data message passes through. The corresponding layer (e.g., the application layer or the convergence layer, etc.) of the target communication device 404 is used to compare and identify the message based on the message information (e.g., the additional message identifier or the additional sequence number) in each data message. The communication device-based method has no impact on the network.

[0135] Optionally, in the case where a repetition mode is selected at the source communication device 402, the source communication device 402 is used to generate a repetition identifier (ID) set for the repeated data message. The repetition ID is stored (i.e., retained) in the header of each data message, regardless of which radio access technology, communication protocol, or wireless link is used in two or more different paths through which the data message passes. The convergence layer or V2X layer (in the case of V2V communication) can be used to generate a repetition ID at the source communication device 402 and reorder or filter the received data messages at the corresponding convergence layer of the target communication device 404. The generation of such a repetition ID enables the unique identification of the repeated data message at the target communication device 404, regardless of which path or intermediate protocol and network node the data message passes through. Similarly, a message ID can be set for the divided data message retained in the data message during the entire communication process, which is used to uniquely identify the divided data message at the target communication device 404.

[0136] In the network-based method, the network is enabled to retain the message information (e.g., message identifier or sequence number) set at a specific network layer (e.g., PDCP, SDAP, or other network layer) of the source communication device 402 on the end-to-end network. The network entity 600 (e.g., base station) is used to map the uplink sequence number of each data packet obtained from the source communication device 402 to the downlink sequence number according to the message information. Optionally, the network-based method has a network impact because it involves signaling the network to retain the message information in the header of each data packet throughout the end-to-end network.

[0137] Figure 8 FIG. 8 is a diagram showing an exemplary scenario 800 for performing multipath communication using different wireless access technologies provided by an embodiment of the present invention. Figures 1 to 3 , FIG. 4A to FIG. 4E , Figure 5 , Figure 6 and Figure 7 Component Description Figure 8 . refer to Figure 8 , an application layer 802A of the source communication device 402 and a corresponding application layer 802B of the target communication device 404 are shown. A control circuit 428 of the source communication device 402 and a control circuit 438 of the target communication device 404 are also shown.

[0138] According to an embodiment, the control circuit 428 of the source communication device 402 is used to provide a first group of data packets in a plurality of data packets to the target communication device 404 through a first path and provide a second group of data packets in a plurality of data packets to the target communication device 404 through a second path. In this embodiment, the first path uses a first radio access technology (RAT-1) and the second path uses a second radio access technology (RAT-2) different from RAT-1. In this case, the first path and the second path correspond to different device-to-device communications using different radio access technologies (e.g., NR PC5 interface and LTE PC5 interface as shown in the figure).

[0139] In one example, in the case where the split mode is selected at the source communication device 402, the control circuit 428 is used to set a sequence number (i.e., a dedicated sequence number) for each data message at the application layer 802A, regardless of which radio access technology (i.e., RAT-1 or RAT-2) is used for data communication. The RAT can be, for example, LTE, 5G, etc. The corresponding application layer 802B of the target communication device 404 is used to check the sequence number of each data message obtained from the source communication device 402. The control circuit 438 of the target communication device 404 is used to reorder the multiple data messages obtained in the first path and the second path (i.e., through different radio access technologies) in the split mode at the corresponding application layer 802B according to the sequence number associated with each of the multiple data messages. Alternatively, instead of the application layer 802A, the sequence number can be set using any other network layer other than the convergence layer, the V2X layer, or the access stratum (AS). Then, the same network layer used to set the sequence number is used at the target communication device 404 to check the sequence number and perform reordering accordingly.

[0140] In another example, in the case where the repetition mode is selected at the source communication device 402, the control circuit 428 is used to set a sequence number (i.e., attach a dedicated sequence number) for each data message at the application layer 802A, regardless of which radio access technology (i.e., RAT-1 or RAT-2) is used for data communication. In addition, at the application layer 802A (or the convergence layer, or the V2X layer in the case of a vehicle), a repetition ID can be assigned to the repetitive data message (e.g., the second group of data messages can have the same payload as the first group of data messages). The control circuit 438 of the target communication device 404 is used to identify the repetitive data message according to the repetition ID, even if the multiple data messages are obtained from the source communication device 402 via different radio access technologies (i.e., via the NR PC5 interface and the LTE PC5 interface). The control circuit 438 is used to filter the repetitive data messages from the multiple data messages received at the target communication device at the corresponding application layer 802B (or the convergence layer, or the V2X layer in the case of a vehicle) based on the message information (e.g., the repetition ID and the dedicated sequence number).

[0141] Fig. 9 An exemplary scenario 900 for performing multipath communication using message repetition and segmentation at the PDCP layer provided by an embodiment of the present invention is shown. FIG. 4A to FIG. 4E , Figure 5 , Figure 6 , Figure 7 , Figure 8 Component Description Fig. 9 . refer to Fig. 9 , the SDAP layer 902A, PDCP layer 904B, RLC layer 906A, and MAC layer 908A associated with the cellular interface (e.g., Uu interface) of the user plane protocol stack in the source communication device 402 are shown. Similarly, the corresponding network layers associated with the corresponding Uu interface are shown in the target communication device 404, such as the SDAP layer 902B, PDCP layer 904B, RLC layer 906B, and MAC layer 908B. In addition to the network layers associated with the Uu interface, the network layers associated with the sidelink communication (e.g., sidelink (SL) RLC 910A and SL MAC 912A) are also shown in the source communication device 402 and the target communication device 404 (e.g., SL RLC 910B and SL MAC 912B). The control circuit 428 of the source communication device 402 and the control circuit 438 of the target communication device 404 are also shown.

[0142] According to the present embodiment, the repetition or division of the data message is described with respect to the PDCP layer 904A rather than the upper layer (e.g., the application layer, the convergence layer, or the V2X layer in the case of the vehicle). However, it should be understood that the repetition or division of the data message can be implemented at different network layers (e.g., the SDAP layer 902A). In the present embodiment, in the repetition mode, when repetition is performed at the PDCP layer 904A of the source communication device 402, the data message with the same PDCP header (i.e., the same PDCP SN) is used for transmission through a cellular communication path (e.g., through a Uu interface) and a sidelink communication path (e.g., a PC5 interface). Therefore, the uplink PDCP SN is the same as the sidelink PDCP SN. However, the uplink PDCP SN still needs to be the same as the downlink PDCP SN in order to efficiently and error-freely send data from the source communication device 402 to the target communication device 404 in multipath communication. Typically, in conventional systems, the PDCP SN of a given data message in an uplink transmission may be different from the PDCP SN of the same given message in a downlink transmission. Therefore, the source RAN node 504 is used to map the uplink PDCP SN received from the source communication device 402 with the downlink PDCP SN of each data packet in the first set of data packets received at the source RAN node 504. The mapping of the uplink PDCP SN with the downlink PDCP SN is to solve the problem of incorrect ordering and enable the target communication device 404 to compare (or match) the data packets obtained through the cellular communication path 510 with the data packets obtained through the sidelink communication path 516. It should be understood that the mapping between the uplink PDCP SN and the corresponding downlink PDCP SN needs to be completed by the RAN (e.g., the source RAN node 504 and the target RAN node 508) and the core network entity 506 of the cellular network 502 to compare the data packets. The source RAN node 504 is also used to attach the uplink PDCP SN obtained from the source communication device 402 to the core network protocol-based header (e.g., GTP-U header) of each received data packet in the first set of data packets. In one example, for a specific service flow (QFI), the source RAN node 504 appends the uplink PDCP SN to the GTP-U header of the data packet sent through, for example, the N3 interface.

[0143] It should be noted that GTP-U is responsible for carrying data within the GPRS core network and between the RAN (for example, the source RAN node 504 and the target RAN node 508) and the core network entity 506. Data transmitted in the form of data packets can have multiple formats, such as the fourth version of the Internet Protocol (Internet Protocol version 4, IPv4) format, the sixth version of the Internet Protocol (Internet Protocol version 6, IPv6) format, the point-to-point protocol (point-to-point protocol, PPP) format, etc. In addition, the source RAN node 504 sends each received data packet of the first group of data packets to the core network entity 506, and each received data packet of the first group of data packets has a GTP-U header including the attached uplink PDCP SN. The GTP-U header including the attached uplink PDCP SN is a modified GTP-U header including the attached uplink PDCP SN, as an extension of the header structure of the GTP-U header. Fig.10 An example of a GTP-U header is described in . The uplink PDCP SN is physically forwarded by the core network entity 506 of the first path 406. In addition, the user plane function (UPF) node retains the PDCP SN in the GTP-U header transmitted on the N3 interface or the N9 interface. Therefore, the GTP-U header is a modified GTP-U header, which at least includes message information, such as the uplink PDCP SN.

[0144] Fig.10 FIG. 1 shows an exemplary structure of a GPRS tunneling protocol user plane (GTP-U) header 1000 provided by an embodiment of the present invention. Figures 1 to 3 , FIG. 4A to FIG. 4E , Figures 5 to 9 Component Description Fig.10 . refer to Fig.10 , shows an example of a core network protocol-based header (e.g., GTP-U header 1000).

[0145] The GTP-U header 1000 includes various fields according to the 3GPP specification, such as a "message type" reserved for the type of data present in the data message. For example, the message type can be text, image, audio, or video. The GTP-U header 1000 may also include fields such as the length of the data message (i.e., measured in bits), a "tunnel endpoint identifier", a "sequence number", etc. In addition, the GTP-U header 1000 also includes a new extension header type field 1002.

[0146] According to an exemplary implementation, the new extension header type field 1002 is used for information associated with a data message that can be sent via an N3 interface between a RAN node (e.g., a source RAN node 504) and a user plane function (UPF) or via an N9 interface between two UPFs (e.g., an intra-PLMN interface or an inter-PLMN interface), such as a repetition mode or a partitioning mode. The new extension header type field 1002 is enhanced or extended to include, for example, an uplink PDCP SN and a quality of service flow identifier (QFI). Optionally, in another implementation, on the N3 (and / or N9) interface of the 5G cellular network, the uplink PDCP SN is attached to the 5G encapsulation header to reduce changes in the header of the data message in the e2e network.

[0147] Activating multipath functionality: There are two options for activating the multipath functionality, for example, in a network-based approach (or scheme). The first option is to activate on a session level, and the second option is to activate on a per-data packet basis. In the first option, a signal is sent to the radio access network node (e.g., base station, such as gNB) and the user plane function (UPF) at the time of protocol data unit (PDU) session establishment or modification to provide specific processing for uplink data packets and downlink data packets through various network nodes and interfaces at the session level. For example, Fig.11 In the second option, the multipath function is activated according to an indicator in the header of each data message in the first set of data messages to provide specific processing for uplink data messages and downlink data messages through various network nodes and interfaces on a per data message basis. For example, in Fig.12 The activation of the multipath function according to the indicator in the header of each data message is described in detail.

[0148] Fig.11 FIG. 11 is a timing diagram 1100 showing a portion of a protocol data unit (PDU) session establishment process provided by an embodiment of the present invention. Figure 1 , Figure 2 , Figure 3 , FIG. 4A to FIG. 4E , Figure 5 , Figure 6 , Figure 7 , Figure 8 , Fig. 9 and Fig.10 Component Description Fig.11 . refer to Fig.11 , showing user equipment (UE) 1102, radio access network / access network (RAN / AN) 1104, access and mobility management function (AMF) 1106, user plane function (UPF) 1108, session management function (SMF) 1110, policy control function (PCF) 1112, unified data management (UDM) 1114 and data network 1116. UE 1102 corresponds to source communication device 402. RAN 1104 corresponds to source RAN node 504 ( Figure 5 ).

[0149] The timing diagram 1100 describes a portion of a PDU session establishment process that complies with the 3GPP specification. In an exemplary implementation, some operations in the timing diagram 1100 involving signaling from the SMF 1110 to the RAN 1104 and the UPF 1108 can be enhanced (or extended) to enable multipath functionality at one or more network entities based on an indicator in a signaling message sent by the source communication device 402 (e.g., via control plane signaling). For example, the signaling from the SMF 1110 to the RAN 1104 (e.g., steps 1124 and 1126) and to the UPF 1108 (e.g., step 1134A) can be enhanced (i.e., extended) so that the uplink sequence number received from the source communication device 402 in a specified network layer (e.g., PDCP layer) is the same as the downlink sequence number in the specified network layer. Specifically, the signaling from SMF 1110 to RAN 1104 may be enhanced (i.e., extended) to enable a sequence number (e.g., PDCP SN) received in a specific network layer to be transmitted in N3 in an uplink data message, and further enable the uplink SN (e.g., downlink PDCP SN) in the specified network layer to be used for the downlink message. In addition, in the timing diagram 1100, the signaling from SMF 1110 to UPF 1108 may be extended to enable UPF 1108 to forward the received data message to the appropriate QFI in the downlink PDU session, the received data message including a modified core network protocol-based header (e.g., a modified GTP-U header) with an attached uplink sequence number.

[0150] In the timing diagram 1100, in step 1118, the process of PDU session establishment (or modification) is described according to the selection of UPF 1108 by SMF 1110. It should be understood by those skilled in the art that various steps may be performed before step 1118. For example, a PDU session establishment request, SMF selection by AMF, signaling from AMF to SMF (i.e., in the form of Nsmf_PDUSession_CreateSMContext request), retrieval of session management subscription data by SMF (if not available), signaling from SMF to AMF (i.e., in the form of Nsmf_PDUSession_CreateSMContext response), etc. (e.g., as specified in 3GPP-23.502).

[0151] In step 1120, SMF 1110 initiates a session management policy association modification between SMF 1110 and PCF 1112. In step 1122A, an N4 session establishment / modification request is sent from SMF 1110 to UPF 1108. In step 1122B, an N4 session establishment or modification response is sent from UPF 1108 to SMF 1110. In step 1124, Namf_communication_N1N2message transmission is performed from SMF 1110 to AMF 1106. In the case that N2 session management (SM) information is not included in step 1124, the following steps 1130 to 1134B and step 1136 may be omitted. Beneficially, in an exemplary implementation of the present invention, the Namf_communication_N1N2 message transmission is enhanced and extended to enable a sequence number (e.g., PDCP SN) received in a specific network layer to be transmitted in N3 in an uplink data message. In step 1126, an N2 PDU session request is sent from AMF 1106 to RAN 1104. In an exemplary implementation, the N2 PDU session request is also enhanced and extended to enable the uplink SN (e.g., downlink PDCP SN) in the specified network layer to be used for downlink messages (in downlink transmission). In step 1128, the N2 PDU session request is accepted. In step 1130, an N2 PDU session request confirmation is sent from RAN 1104 to AMF 1106. In step 1132, a Nsmf_PDUSession_updateSMContext request is sent from AMF 1106 to SMF 1110. In step 1134A, an N4 session modification request is sent from the SMF 1110 to the UPF 1108. In an exemplary implementation, the signaling from the SMF 1110 to the UPF 1108 may be enhanced and extended to enable the UPF 1108 to forward the received data packet including the modified core network protocol-based header (e.g., modified GTP-U header) with the attached uplink sequence number to the appropriate QFI in the downlink PDU session. The N4 session modification request is used to enable the UPF 1108 to forward the received data packet including the modified core network protocol-based header (e.g., modified GTP-U header) with the attached uplink sequence number to the appropriate QFI in the downlink PDU session. In step 1134B, the SMF 1110 receives the N4 session modification response. In step 1136, the Nsmf_PDUSession_updateSMContext response is sent from SMF 1110 to AMF 1106.In step 1138, the Nsmf_PDUSession_SMContext_status_notify service from SMF 1110 to AMF 1106 is executed.

[0152] In conventional systems and methods and existing standards, there are various problems, such as different message identifiers for different protocols and different protocol layers and network entities (e.g., RAN part, core network part, etc.). In the first example, IPv4 has an identifier (ID) (i.e., IP ID) enabled for message segmentation, but such IP ID is not included in IPv6. In the second example, the QoS Flow Identifier (QFI) enables QoS granularity differentiation in a PDU session. Typically, a QoS Flow ID (QFI) is used to identify QoS flows in a 5G (NR)-enabled device. Typically, user plane traffic with the same QFI within a PDU session receives the same traffic forwarding treatment (e.g., scheduling, admission threshold, etc.). The QFI is carried in the encapsulation header on the N3 (and N9) interface, i.e., there is no change in the message header in the e2e network. The QFI is used for all PDU session types. The QFI is unique in a PDU session. The QFI can be dynamically allocated or equal to the 5QI (i.e., 5G QoS feature). However, in such conventional methods and systems, there is no per-message processing. In the third example, currently, in uplink transmission, the PDCP SN is only available at the RAN (e.g., RAN 1104) from UE 1102 to the base station, while another PDCP SN can be set in the downlink transmission from the base station to the user equipment (i.e., the wireless communication device). This depends on the message disorder, the path taken by the data message, etc. In the fourth example, the core network message identifier (in N3) is included in the user plane, and when the transmission order of the data message must be preserved, the added SN for transmitting the (T)-PDU ​​is transmitted through the GTP-U tunnel (GTP-U header). This field is an optional field in the G-PDU and consists of the GTP-U header within the GPRS backbone network plus the T-PDU. However, in conventional methods and systems, the focus is on part of the N3 transmission (i.e., from RAN to UPF, or from UPF to RAN), and there is no direct connection / correlation with the RAN message ID. Furthermore, in conventional methods and apparatus, there is no end-to-end tracking, mapping, or correlation between (R)AN 1104 and core network messages. Therefore, various steps (e.g., steps 1122A to 1128) and step 1134A of timing diagram 1100 are enhanced and expanded to enable multipath functionality and address issues associated with conventional methods and systems as described above.

[0153] Fig.12FIG. 1 shows an exemplary indicator in a header of a data message provided by an embodiment of the present invention. Figure 1 , Figure 2 , Figure 3 , FIG. 4A to FIG. 4E , Figures 5 to 11 Component Description Fig.12 . refer to Fig.12 , shows a PDCP header structure 1200. The PDCP header structure 1200 includes a plurality of fields, such as a plurality of reserved fields 1202, 1204, and 1206, and a field for a MAC address of a data packet.

[0154] According to an embodiment, any one or more of the plurality of reserved fields 1202, 1204, and 1206 may be used as an indicator (e.g., a flag) to enable RAN mapping of an uplink PDCP SN to a downlink PDCP SN of a data message. In one example, the reserved field 1202 may be set by the source communication device 402 to a specific bit value (e.g., a bit value of "1") in a binary bit value ("0" or "1") to signal the network entity 600 (e.g., the source RAN node 504) to activate the multipath function to enable mapping of the uplink PDCP SN to the downlink PDCP SN. Thus, the source RAN node 504 is used to map the uplink PDCP SN to the downlink PDCP SN according to the indicator (i.e., in this example, the bit value "1" in the reserved field 1202). In another example, the source communication device 402 is further used to set the reserved field 1204 for the uplink data message in the PDCP header structure 1200 to an indication of selecting a repetition mode at the source communication device 402. Therefore, according to this indication, the target communication device 404 is used to determine that the multiple data packets obtained from the source communication device 402 through two or more different paths include duplicate data packets. Advantageously, using multiple reserved fields 1202, 1204 and 1206 as indicators can achieve packet processing of uplink data packets and downlink data packets instead of stream processing without modifying the existing PDCP header, thereby minimizing the implementation cost.

[0155] Fig.13 An exemplary scenario 1300 for performing vehicle-to-vehicle (V2V) multipath communication provided by an embodiment of the present invention is shown. Figure 1 , Figure 2 , Figure 3 , FIG. 4A to FIG. 4E , Figures 5 to 12 Component Description Fig.13 . refer to Fig.13, an exemplary scenario 1300 is shown including a source vehicle 1302 and a target vehicle 1304 moving on a road portion 1306. The source vehicle 1302 includes an electronic control unit (ECU) 1308, and the target vehicle 1304 includes an ECU 1310. A source base station 1312, a target base station 1314, a cellular communication path 1316, and a sidelink communication path 1318 are also shown.

[0156] According to the exemplary scenario 1300, the source vehicle 1302 and the target vehicle 1304 correspond to the source communication device 402 and the target communication device 404, respectively. Figure 4A ). The source base station 1312 and the target base station 1314 correspond to the source RAN node 504 and the target RAN node 508, respectively. Figure 5 ). The source vehicle 1302 may be within the communication range to establish D2D communication with each other. The user of the source vehicle 1302 wishes to send data to the target vehicle 1304.

[0157] According to an embodiment, the ECU 1308 of the source vehicle 1302 is used to select a repetition mode or a division mode to send multiple data messages to the target vehicle 1304 through the cellular communication path 1316 and the side link communication path 1318. The ECU 1308 of the source vehicle 1302 is used to provide a first group of data messages in the multiple data messages to the target vehicle 1304 through the cellular communication path 1316 and provide a second group of data messages in the multiple data messages to the target vehicle 1304 through the side link communication path 1318. In other words, multiple V2X messages communicate through different radio access technologies, radio links, interfaces or communication protocols to improve the QoS of communication between the two vehicles, thereby improving the reliability of V2V communication. The header of each data message includes message information indicating the association between the multiple data messages. The first group of data messages passes through various network entities (e.g., the source base station 1312) and neighboring base stations (e.g., the target base station 1314). In some cases, the first group of data messages may also pass through the core network entity.

[0158] According to an embodiment, the source base station 1312 is used to obtain a first group of data messages from the source vehicle 1302. The header of each data message in the first group of data messages includes message information. The source base station 1312 is used to map the uplink sequence number received in the specified network layer (e.g., PDCP layer or other network layer) to the downlink sequence number of each data message in the received first group of data messages according to the message information. When the target vehicle is within the communication range of the source base station 1312 during communication, the source base station 1312 is used to provide each received data message including the message information in the first group of data messages to the target vehicle 1304. When the target vehicle 1304 exceeds the communication range of the source base station 1312, the source base station 1312 is used to provide the first group of data messages including each received data message of the data message to an adjacent base station (e.g., the target base station 1314).

[0159] According to an embodiment, the ECU 1310 of the target vehicle 1304 is used to identify the first group of data messages received through the cellular communication path 1316 and the second group of data messages received through the sidelink communication path 1318 according to the message information. Since the message information in the header of each data message does not change, no matter which radio access technology, communication protocol or wireless link is used in two or more different paths (i.e., in this case, the cellular communication path 1316 and the sidelink communication path 1318), the quality of service (quality-of-service, QoS) of data communication between the source vehicle 1302 and the target vehicle 1304 is improved. For example, in the case where the multiple data messages obtained through two or more different paths include different data messages with different loads (i.e., in the split mode), the data throughput is improved and the data communication delay is reduced. In addition, in the case where the multiple data messages obtained through two or more different paths include duplicate data messages with the same load copy, the reliability of the data communication between the source vehicle 1302 and the target vehicle 1304 is significantly improved. Beneficially, such V2V multipath communication between the source vehicle 1302 and the target vehicle 1304 is used to improve road safety through an efficient and reliable mechanism for sharing alerts and other data (e.g., text, images, audio, or video) simultaneously over two or more different paths between the source vehicle 1302 and the target vehicle 1304.

[0160] Without departing from the scope of the invention as defined by the appended claims, the embodiments of the invention described above may be modified. "Including", "combining", "having", "being", etc., used to describe and claim the present invention, are intended to be interpreted in a non-exclusive manner, that is, to allow items, components or elements that are not explicitly described to exist. References to the singular should also be interpreted as being related to the plural. The word "exemplary" used herein means "as an example, instance or illustration". Any embodiment described as "exemplary" is not necessarily interpreted as being more preferred or more advantageous than other embodiments, and / or excluding the combination of features of other embodiments. The word "optionally" used herein means "provided in some embodiments and not provided in other embodiments". It should be understood that some features of the present invention described in the context of a single embodiment for the sake of clarity may also be provided in combination in a single embodiment. On the contrary, the various features of the present invention described in the context of a single embodiment for the sake of brevity may also be provided separately, in any suitable combination, or suitable for any other described embodiment of the present invention.

Claims

1. A method (100) for performing multipath communication at a target communication device (404), characterized in that: The method (100) comprises: A plurality of data packets are obtained from a source communication device (402) through two or more different paths, wherein a header of each of the plurality of data packets includes packet information, wherein: The message information indicates the association between the multiple data messages; The message information in each data message of the source communication device (402) is the same as the message information in each data message of the target communication device (404); The multiple data messages include different data messages with different payloads or duplicate data messages with copies of the same payload; According to the message information, a first group of data messages among the multiple data messages received through the first path (406) and a second group of data messages among the multiple data messages received through the second path (408) are identified, and the multiple data messages are reordered according to the sequence numbers of the multiple data messages, where the sequence number of each data message is obtained by mapping the uplink sequence number of the data message to the downlink sequence number according to the message information by the network entity (600) of the corresponding path.

2. The method (100) according to claim 1, characterized in that: At least one of the first path or the second path corresponds to a device-to-device communication between the source communication device (402) and the target communication device (404).

3. The method (100) according to claim 1 or 2, characterized in that: The first path (406) of the two or more different paths is a cellular communication path (510), the second path (408) of the two or more different paths is a sidelink communication path (516) corresponding to device-to-device communication, and the source communication device (402) and the target communication device (404) are at least one of the following: a vehicle, an electronic device used in a vehicle, or a portable electronic device.

4. The method (100) according to claim 3, characterized in that: Also includes: The target communication device (404) filters duplicate data messages from the multiple data messages received at the target communication device (404) according to the message information.

5. The method (100) according to claim 1, 2 or 4, characterized in that: In the partitioning mode, the plurality of data packets include different data packets obtained through the first path (406) and the second path (408).

6. A method (200) for performing multipath communication at a source communication device (402), characterized in that: The method (200) comprises: A first group of data packets among a plurality of data packets is provided to a target communication device (404) via a first path (406) and a second group of data packets among the plurality of data packets is provided to the target communication device (404) via a second path (408), wherein a header of each data packet includes message information indicating an association between the plurality of data packets, and the message information is used by network entities (600) of the first path (406) and the second path (408) to map an uplink sequence number of a data packet to a downlink sequence number; wherein the plurality of data packets include different data packets with different payloads or duplicate data packets with copies of the same payload.

7. The method (200) according to claim 6, characterized in that: At least one of the first path (406) or the second path (408) corresponds to a device-to-device communication between the source communication device (402) and the target communication device (404), and wherein the message information in each data message of the source communication device (402) is the same as the message information in each data message of the target communication device (404).

8. The method (200) according to claim 6 or 7, characterized in that: Also includes: The source communication device (402) selects a repetition mode or a partitioning mode to send the plurality of data packets to the target communication device (404) through two or more different paths, wherein the repetition mode or the partitioning mode is selected before a data session starts or during a data session.

9. The method (200) according to claim 8, characterized in that: Also includes: The source communication device (402) sends the first group of data packets to the network entity (600) via the first path (406) in an uplink transmission (512), and sends the second group of data packets to the target communication device (404) via the second path (408) as repeated data packets according to the selected repetition mode, wherein in the repetition mode, the payload of the first group of data packets is the same as the payload of the second group of data packets.

10. The method (200) according to claim 8, characterized in that: Also includes: The source communication device (402) sends the first group of data packets to the network entity (600) via the first path (406) in an uplink transmission (512), and sends the second group of data packets to the target communication device (404) via the second path (408), wherein in the partitioning mode, the load of the first group of data packets is different from the load of the second group of data packets.

11. The method (200) according to claim 9 or 10, characterized in that: The header of each data packet of the plurality of data packets or the signaling message sent by the source communication device (402) to at least one of the network entity (600) or the target communication device (404) when the data session is established or updated includes an indicator, The indicator indicates that a multipath function is enabled at the network entity (600) or at the target communication device (404).

12. A method (300) for performing multipath communication at a network entity (600), characterized in that: The method comprises: Acquire a first group of data packets from a source communication device (402), wherein a header of each data packet in the first group of data packets comprises packet information, wherein the packet information indicates an association between the first group of data packets; According to the message information, mapping the uplink sequence number of each data message in the first group of data messages to a downlink sequence number; Each received data packet in the first set of data packets including the packet information is provided to at least one of a target communication device (404) or another network entity based on the mapping of the uplink sequence number to the downlink sequence number.

13. The method (300) according to claim 12, characterized in that: The uplink sequence number is received from the source communication device (402) in a specified network layer, and the uplink sequence number is mapped to the downlink sequence number in the specified network layer, wherein the specified network layer is at least one of a packet data convergence protocol layer, a service data adaptation protocol layer, or another network layer.

14. The method (300) according to claim 12 or 13, characterized in that: Also includes: The network entity (600) appends the uplink sequence number received from the source communication device (402) to a header based on a core network protocol of each received data message in the first group of data messages; The network entity (600) sends each received data packet in the first group of data packets to the core network entity (506), and each received data packet in the first group of data packets has the core network protocol-based header including the attached uplink sequence number, wherein the core network protocol-based header including the attached uplink sequence number is a modified core network protocol-based header, and the modified core network protocol-based header includes the attached uplink sequence number as an extension in the core network protocol-based header structure.

15. The method (300) according to claim 14, characterized in that: The core network protocol-based header is a general packet radio service tunneling protocol user plane header (1000).

16. The method (300) according to any one of claims 12, 13 and 15, characterized in that: Also includes: Before downlinking the received data packets in the first set of data packets to the target communication device (404), the network entity (600) sets the retrieved uplink sequence number in each received data packet as a downlink sequence number (514).

17. The method (300) according to any one of claims 12, 13 and 15, characterized in that: Also includes: The network entity (600) enables a multipath function according to an indicator in the header of each data message in the first group of data messages or in a signaling message sent by the source communication device (402), wherein enabling the multipath function comprises: - storing the message information in each data message of the first set of data messages received at the network entity (600), and multiplexing the message information to further provide each received message to the target communication device (404); or - routing each data packet of the first set of data packets having packet information to another network entity, the network entity multiplexing the packet information to further provide each received packet to the target communication device (404) via the network entity (600) or another network entity.

18. A target communication device (404) for performing multipath communication, characterized in that: include: A control circuit (438) for: Acquire multiple data messages from a source communication device (402) through two or more different paths, wherein a header of each data message in the multiple data messages includes message information, The message information indicates the association between the multiple data messages; The message information in each data message of the source communication device (402) is the same as the message information in each data message of the target communication device (404); The multiple data messages include different data messages with different payloads or duplicate data messages with copies of the same payload; According to the message information, a first group of data messages among the multiple data messages received through the first path (406) and a second group of data messages among the multiple data messages received through the second path (408) are identified, and the multiple data messages are reordered according to the sequence numbers of the multiple data messages, where the sequence number of each data message is obtained by mapping the uplink sequence number of the data message to the downlink sequence number according to the message information by the network entity (600) of the corresponding path.

19. A source communication device (402) for performing multipath communication, characterized in that: include: A control circuit (428) for: Providing a first group of data messages among a plurality of data messages to a target communication device (404) via a first path (406) and providing a second group of data messages among a plurality of data messages to the target communication device (404) via a second path (408), wherein a header of each data message includes message information indicating association between the plurality of data messages, and the message information is used by network entities (600) of the first path (406) and the second path (408) to map uplink sequence numbers of data messages to downlink sequence numbers; The multiple data messages include different data messages with different payloads or duplicate data messages with copies of the same payload.

20. A network entity (600) for performing multipath communication, characterized in that: include: The physical control circuit (602) is used to: Acquire a first group of data packets from a source communication device (402), wherein a header of each data packet in the first group of data packets comprises packet information, wherein the packet information indicates an association between the first group of data packets; According to the message information, mapping the uplink sequence number of each data message in the first group of data messages to a downlink sequence number; Based on the mapping of the uplink sequence number to the downlink sequence number, each received data packet in the first set of data packets including the packet information is provided to at least one of a target communication device (404) or another network entity.

21. A computer program product comprising a non-transitory computer-readable storage medium, characterized in that The non-transitory computer-readable storage medium stores computer-readable instructions that are executed by a computerized device including processing hardware for performing the method according to any one of claims 1 to 5.

22. A computer program product comprising a non-transitory computer-readable storage medium, characterized in that The non-transitory computer-readable storage medium stores computer-readable instructions that are executed by a computerized device including processing hardware for performing the method according to any one of claims 6 to 11.

23. A computer program product comprising a non-transitory computer-readable storage medium, characterized in that The non-transitory computer-readable storage medium stores computer-readable instructions that are executed by a computerized device including processing hardware for performing the method according to any one of claims 12 to 17.

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