Method and system for improving the reliability and throughput of end-to-end traffic over cellular relay devices

Abstract

This invention relates to improving reliability and throughput when using relay devices such as cellular relay devices for side-link relay communication in cellular networks, or other relay devices such as access devices or satellites.

Description

[[Technical Field]]

[0001] The present invention relates to a communication device, a base station device, and a method for end-to-end packet duplication and / or data splitting / aggregation that improve reliability and throughput when using relay devices such as cellular relay devices including sidelink relay communication in cellular networks, or other relay devices such as access devices or satellites. [[Background Art]]

[0002] In the 3GPP (registered trademark) specifications 23.304 and 24.501 for 5G networks, the so-called Proximity Service (ProSe) function is defined, among other things, to enable connectivity for cellular communication devices (e.g., UEs) that are temporarily not included in the coverage of an access device (gNB). This specific function is called ProSe UE-to-Network relay or relay UE. A relay UE is a communication device that helps another UE communicate with a gNB (i.e., an access device) by bidirectionally relaying application and network data traffic between this another UE and the gNB. Local communication between a relay UE and another UE is called D2D communication, sidelink communication, or PC5 communication. The abbreviation "PC5" designates the interface for sidelink communication defined in ProSe. Furthermore, the abbreviation "UL" is used for the uplink direction from a communication device (e.g., UE) to an access device (e.g., gNB), the abbreviation "DL" is used for the downlink direction from an access device (e.g., gNB) to a communication device (e.g., UE), and the abbreviation "SL" is used for sidelink communication between two or more communication devices (e.g., UEs). When a relay relationship is established, a UE can connect via the relay UE and serve the role of a "remote UE". This situation means that the remote UE has an indirect network connection to the CN, in contrast to a direct network connection which is the normal case (see 3GPP (registered trademark) specification TS22.261 v16.10.0).

[0003] Furthermore, 3GPP® specifications TR23.733 v15.1.0 and TR36.746 v15.1.1 provide research on architectural enhancements that enable IoT devices (in the role of remote UEs) to operate at very low power by connecting to wider networks using relay UEs, for example. Because relay UEs are physically very close, they can be reached using very low power transmissions. This work also includes improvements to the safety, speed, and stability of ProSe. These extensions to ProSe are called Enhanced ProSe ("eProSe"). One of the improvements proposed in eProSe is an enhanced relay architecture that operates at the second protocol layer (i.e., L2) and aims to provide end-to-end Internet Protocol (IP) and Packet Data Convergence Protocol (PDCP) packet transmission to remote communication devices for application and user data. The advantage of this architecture is that remote communication devices become directly visible as registered entities within the CN, which is relevant for monitoring and billing purposes, and also relates to improved control by access devices via communication devices.

[0004] Current 3GPP® sidelink relay solutions still have several challenges and limitations, particularly in multipath relay scenarios. For example, current solutions do not address means of efficiently splitting or aggregating data packets at source UEs, relay UEs, and base stations to optimize end-to-end performance. Furthermore, current solutions do not consider means of handling packet duplication or retransmission in multipath relay scenarios, which can cause unnecessary overhead and interference. Additionally, current solutions do not provide a flexible and scalable framework to support different types of relay devices, such as cellular relay devices, access devices, or satellites, which have varying capabilities and requirements. Therefore, there is a need for improved methods and systems for end-to-end packet duplication and aggregation data splitting / aggregation in multipath relay scenarios, as well as a versatile and extensible mechanism to support various relay devices and technologies.

[0005] 3GPP® standardized sidelink relay functionality for 5G NR in Release 17 (R17) (see RP-212819), which supports L2 UE-to-Network (U2N) relaying to allow remote UEs (User Equipment) outside base station coverage to connect to the cellular network via a relay UE, similar to a normal in-network coverage UE, or to allow remote UEs at the base station edge to connect to the cellular network via a relay UE with better connectivity to the base station, thereby improving connectivity for remote UEs to base stations. The main benefits of R17 sidelink relay are expanded network coverage and improved power efficiency for UEs outside cell coverage or at the edge.

[0006] 3GPP® further enhances sidelink relay capabilities in R18 (see RP-223501), supporting multi-path relay of remote UEs within base station coverage to simultaneously connect to the network via direct (Uu) and indirect (U2N) paths, improving reliability, robustness, and throughput. In addition, UE-to-UE (U2U) relay, which was considered in R17, has also been standardized for sidelink coverage extension.

[0007] In use cases for high-reliability, low-latency communication (URLLC) using sidelink relays, remote UEs such as industrial Internet of Things (IoT) devices, XR immersive communication devices, and haptic communication devices need additional reliability and very low latency to transmit data via the relay UE to a base station (in the case of U2N relays) or a target remote UE (in the case of U2U relays).

[0008] Another use case for high-data-rate video transmission using sidelink relays is when remote UEs, such as Extended Reality (XR) immersive communication devices (i.e., for use in combinations of real and virtual environments using computer technologies including augmented reality (AR), virtual reality (VR), and mixed reality (MR)), or vehicle-to-vehicle / vehicle-to-infrastructure (V2X) devices for high-data-rate local sensor data sharing (i.e., for communication between a vehicle and any entity that may affect or be affected by a vehicle), need to transmit large amounts of data to a base station (in the case of U2N relays) or to a target remote UE (in the case of U2U relays) via a relay UE within a very short period of time.

[0009] In another use case, two UEs are connected via one or more satellite links. These satellite links enable direct communication between both UEs. In this use case, improving reliability and throughput is beneficial.

[0010] If the remote UE is within the cell / base station's coverage, the R18 sidelink relay multipath relay may partially solve the two problems mentioned above. Because the R18 sidelink relay multipath relay can be modeled similarly to dual connectivity (DC), the remote UE can have two simultaneous connections to the cell / base station: a direct path and an indirect path. The following design principles have been agreed upon in the ongoing standardization work in 3GPP® RAN2: A replica signaling radio bearer (SRB) can be configured on both paths for the reliability of control plane signaling.

[0011] In the case of a data radio bearer (DRB), for the reliability and robustness of user plane data, a duplicate DRB can be configured on both paths, or a split bearer can be configured to aggregate user plane data that has passed through both paths.

[0012] However, to use sidelink relays and multipath relays to improve reliability, robustness, and / or throughput, the remote UE must be within the direct coverage of the cell / base station. For remote UEs outside the cell / base station coverage in U2N relays, or remote UEs in U2U relays, there are no technologies to improve the end-to-end reliability, robustness, and low latency of URLLC communication between the remote UE and the base station in U2N relays, or between the source remote UE and the target remote UE in U2U relays. Additionally, there are no technologies to enable end-to-end user traffic segmentation and aggregation for high-throughput eMBB (Advanced Mobile Broadband) communication between the remote UE and the base station in U2N relays, or between the source remote UE and the target remote UE in U2U relays. [Overview of the project] [Problems that the invention aims to solve]

[0013] The present invention aims to provide methods and systems for improving the reliability and throughput of end-to-end packet replication and data partitioning / aggregation in 4G, 5G, and future 6G cellular networks that support relays such as side links or satellite relays between source and target nodes via one or more relay nodes in a transmission path, in order to optimize the end-to-end quality of service (QoS, reliability, robustness, latency, jitter, data rate, throughput, etc.) of data traffic.

[0014] As is evident from the description of the problem above, there is no end-to-end packet duplication or data splitting / aggregation scheme that duplicates or splits the data stream of packets or (IP) traffic between the source node and the target node in a transmission path of one or more hops.

[0015] The present invention aims to overcome end-to-end packet replication and data partitioning / aggregation problems so that data stream packets can be transmitted with improved reliability over multiple paths through all hops in the transmission path between a source node and a target node in a wireless network. [Means for solving the problem]

[0016] This objective is achieved by the first communication device described in claim 1, the base station device described in claim 6, the method according to claim 8, and the computer program product described in claim 9.

[0017] According to a first aspect, the present invention relates to a first communication device for a wireless network that supports end-to-end packet replication and / or data partitioning / aggregation over a plurality of hops. This first communication device is Establishing one or more communication paths between the first communication device and the second communication device, Receiving configuration information from another communication device in a wireless network, wherein the configuration information includes at least one parameter relating to end-to-end packet replication and / or data partitioning / aggregation via one or more communication paths between the first communication device and the second communication device, and via one or more communication paths between the first communication device and at least one third communication device and / or at least one third communication device and the second communication device, Based on the configuration information, establish one or more communication paths between the first communication device and at least one third communication device, or Transmitting configuration information to the second communication device, including at least one parameter relating to end-to-end packet replication and / or data partitioning / aggregation, via one or more communication paths between at least one third communication device and the second communication device, or Sending and receiving data between a first communication device and at least one third communication device, and / or between at least one third communication device and a second communication device, via one or more communication paths, by duplicating and / or splitting the data on one or more communication paths between a first communication device and at least one third communication device, and / or between at least one third communication device and a second communication device, according to configuration information. Perform at least one of the following based on the configuration information. It is adapted to perform this action.

[0018] In an alternative embodiment of the first communication device, one or more communication paths between the first communication device and the second communication device are one or more direct wireless connections or radio link control (RLC) channels between the first communication device and the second communication device, and / or one or more indirect wireless connections or relay RLC channels between the first communication device and the second communication device via at least one third communication device.

[0019] In an alternative embodiment of the first communication device, the second communication device is neither a destination endpoint of the transmitted duplicated / split data, nor an originating source of the received duplicated / split data.

[0020] In an alternative embodiment of the first communication device, the at least one parameter related to end-to-end packet duplication via one or more communication paths includes a QoS policy and / or a duplication threshold.

[0021] In an alternative embodiment of the first communication device, the at least one parameter related to data splitting / aggregation via one or more communication paths includes a QoS policy and / or a data splitting threshold.

[0022] In a second aspect, the present invention relates to a base station device in a wireless network that supports end-to-end packet duplication and / or data splitting / aggregation via wireless links to one or more communication devices, the base station device being connected directly to the first communication device if the base station device has a direct communication path with the first communication device, connected indirectly to the first communication device if the base station device has an indirect communication path with the first communication device via one or more second communication devices, configured to establish one or more communication paths between the first communication device and the base station device, and adapted to configure the first communication device and one or more second communication devices with at least one parameter related to end-to-end packet duplication and / or data splitting / aggregation via one or more communication paths between the first communication device and the base station device, and / or between the first communication device or the base station device and the one or more second communication devices.

[0023] In an alternative embodiment of the second aspect, the base station device is establishing one or more communication paths between the first communication device and one or more second communication devices based on configuration information, or transmitting and receiving data between the first communication device, the base station device and one or more second communication devices over one or more communication paths by duplicating and / or splitting data on the one or more communication paths between the first communication device, the base station device and the one or more second communication devices in accordance with configuration information is further adapted to perform at least one of the above based on the configuration information.

[0024] In a third aspect, the present invention relates to a method of end-to-end packet duplication and / or data splitting / aggregation in a wireless network. The method comprises: establishing one or more communication paths between a first communication device and a second communication device; receiving configuration information from another communication device in the wireless network, wherein the configuration information includes at least one parameter related to end-to-end packet duplication and / or data splitting / aggregation via one or more communication paths between the first communication device and the second communication device, and via one or more communication paths between the first communication device and at least one third communication device and / or between the at least one third communication device and the second communication device; based on the configuration information, establishing one or more communication paths between the first communication device and at least one third communication device, or transmitting configuration information including at least one parameter related to end-to-end packet duplication and / or data splitting / aggregation via one or more communication paths between at least one third communication device and the second communication device to the second communication device, or Sending and receiving data between a first communication device and at least one third communication device, and / or between at least one third communication device and a second communication device, via one or more communication paths, by duplicating and / or splitting the data on one or more communication paths between a first communication device and at least one third communication device, and / or between at least one third communication device and a second communication device, according to configuration information. A step of performing at least one of the following based on the configuration information Includes.

[0025] In a fourth aspect, the present invention relates to a computer program product that includes coding means for generating steps of the method of the third aspect when executed on a computer device.

[0026] Furthermore, it should be understood that preferred embodiments of the present invention may be dependent claims with corresponding independent claims or any combination of the above embodiments.

[0027] These and other aspects of the present invention will become apparent from the embodiments described below and will be described with reference to those embodiments. [Brief explanation of the drawing]

[0028] [Figure 1] Figure 1 schematically shows a side-link relay UE-to-network relay. [Figure 2] Figure 2 schematically shows the multi-path relay of the sidelink relay UE-to-network relay in 3GPP® 5G NR R18. [Figure 3] Figure 3 schematically shows the UE-to-UE relay of the 3GPP® 5G NR R18 sidelink relay. [Figure 4] Figure 4 schematically shows PDCP replication of 3GPP® 5G NR R15 / R16 using carrier aggregation on the Uu interface. [Figure 5]Figure 5 schematically illustrates PDCP replication of 3GPP® 5G NR R15 / R16 using dual connectivity on the Uu interface. [Figure 6] Figure 6 schematically illustrates PDCP replication of 3GPP® 5G NR R15 / R16 using dual connectivity and carrier aggregation on the Uu interface. [Figure 7A] Figure 7A schematically shows the end-to-end packet replication scheme of the sidelink relay U2N relay according to the first embodiment. [Figure 7B] Figure 7B schematically shows the end-to-end data partitioning and aggregation scheme of the side link relay U2N relay according to the second embodiment. [Figure 8A] Figure 8A schematically shows the end-to-end packet replication scheme of the sidelink relay U2U relay according to the third embodiment. [Figure 8B] Figure 8B schematically shows the end-to-end data partitioning / aggregation scheme of the side-link relay U2U relay according to the fourth embodiment. [Figure 9] Figure 9 schematically shows the QoS flow and wireless bearer mapping in the end-to-end packet replication and / or data partitioning / aggregation scheme of the sidelink relay U2N relay in the first and / or second embodiments. [Figure 10] Figure 10 schematically shows a protocol stack for end-to-end packet replication and / or data partitioning / aggregation of a sidelink relay U2N relay according to the first and / or second embodiment. [Figure 11] Figure 11 schematically shows the QoS flow and wireless bearer mapping in the end-to-end packet replication and / or data partitioning / aggregation scheme of the sidelink relay U2U relay according to the third and / or fourth embodiment. [Figure 12]Figure 12 schematically shows a protocol stack for end-to-end packet replication and / or data partitioning / aggregation of a sidelink relay U2U relay according to the third and / or fourth embodiment. [Figure 13] Figure 13 schematically shows an end-to-end packet replication and / or data partitioning / aggregation scheme for sidelink relay, multihop relay, and U2N relay according to the fifth embodiment. [Figure 14] Figure 14 schematically shows an end-to-end packet replication and / or data partitioning / aggregation scheme for sidelink relay, multihop relay, and U2U relay according to the sixth embodiment. [Figure 15] Figure 15 schematically shows an end-to-end packet replication and / or data partitioning / aggregation channel between a source node and a target node according to the seventh embodiment. [Figure 16] Figure 16 schematically shows a deployment scenario of an embodiment using two relay devices. [Figure 17] Figure 17 schematically shows the protocol stack for traffic splitting / duplication. [Modes for carrying out the invention]

[0029] Embodiments of the present invention are described below based on a cellular network environment (for example, a 3GPP®-based environment).

[0030] Throughout this disclosure, the abbreviation “gNB” (5G terminology) is intended to mean an access device such as a cellular base station or Wi-Fi® access point. A gNB is part of the Radio Access Network (RAN) and provides an interface to functions within the Core Network (CN). The RAN is part of the wireless communications network. It implements Radio Access Technology (RAT). Conceptually, it exists between communications devices such as mobile phones, computers, or any remotely controlled machines and provides connectivity to their CN. The CN is the core part of the communications network and provides numerous services to clients interconnected via the RAN. More specifically, it manages communications streams across communications networks and, in some cases, other networks. For example, in the case of a 5G cellular core network, the Access Mobility Management Function (AMF) terminates the control planes of different access networks into the 5G CN (5GC) and controls which UEs can access the 5GC and exchange traffic. It also manages the mobility of UEs when roaming from one gNB to another, whenever possible, for session / service continuity. In addition, Information Elements (IEs) specify information (groups) that may be included in signaling messages or data flows sent through the interface (e.g., QoS (Quality of Service) definitions, setup parameters, user identifiers, etc.). Furthermore, the abbreviation "UPF" specifies the user plane function that connects the actual data coming through the RAN to the internet. Furthermore, a Gateway Mobile Location Center (GMLC) is used for active mobile positioning; that is, specific activity on the network is triggered to obtain the subscriber's location in real time. To improve positioning accuracy, the GMLC can connect to additional precise location components within the network. The GMLC includes the necessary functionality to support LCS (Location Services). Multiple GMLCs may exist in a single PLMN (Public Land Mobile Network). The GMLC is the first node that external LCS clients access within the network.

[0031] The Media Access Control (MAC) layer (defined in 3GPP® TS38.321) is one of two sublayers that make up the data link layer. It plays a crucial role in managing radio resources and ensuring efficient communication within 5G networks. It is responsible for moving data from the network interface card to the shared channel. Along with data link control, the MAC layer is responsible for the complete physical addressing of the data link layer.

[0032] Carrier aggregation (CA) Carrier aggregation is a technique that facilitates the efficient use of fragment spectra by aggregating and using multiple component carriers together for transmission to / from a single device.

[0033] Carrier aggregation, first introduced in R10 for 4G LTE, allows for the aggregation of up to five component carriers (CCs) (each potentially with different bandwidths), enabling a maximum transmission bandwidth of 100 MHz. Different numbers of component carriers can be aggregated for downlink and uplink. CCs do not need to be contiguous in frequency; adjacent (contiguous within the band) CCs or non-adjacent (non-contiguous within the band) CCs within the same frequency band, as well as CCs in different frequency bands (interband). R11 provided additional flexibility for the aggregation of TDD (Time Division Duplex) carriers with different downlink and uplink allocations. R12 defined aggregation between FDD (Frequency Division Duplex) carriers and TDD carriers. R13 increased the number of component carriers that could be aggregated from 5 to 32, resulting in a maximum bandwidth of 640 MHz.

[0034] The 5G New Radio (NR) RAT has supported carrier aggregation since its first release, R15. While bandwidth and duplex schemes may differ, it can aggregate up to 16 carriers, achieving an overall transmission bandwidth of up to 16 * 400 MHz = 6.4 GHz.

[0035] The specification describes carrier aggregation using the term "cell." This means that a carrier aggregation-enabled device can receive from and transmit to multiple cells. One of these cells is called the primary cell (PCell). The PCell is the first cell that a device finds and connects to, and once the device enters connected mode, it can configure one or more secondary cells (SCells). SCells can be quickly activated or deactivated in response to changes in traffic patterns.

[0036] Carrier aggregation implies very close coordination among all cells belonging to the same gNB. Scheduling decisions are made jointly by a single joint scheduler within a single MAC entity for all cells to which a device is connected. Carrier aggregation supports both self-scheduling and cross-carrier scheduling.

[0037] Sidelink carrier aggregation For 4G LTE, sidelink multi-carrier operation / carrier aggregation is defined in TR15. When operating in CA mode, a given sidelink MAC protocol data unit (PDU) is transmitted and, if necessary, retransmitted over a single sidelink carrier, allowing multiple MAC PDUs to be transmitted in parallel over different carriers. This provides throughput gains similar to Uu CA (see TR37.985 V17.1.1). LTE sidelink CA supports resource allocation modes 3 and 4.

[0038] In 5G NR R18, 3GPP® has further enhanced sidelinks to support carrier aggregation, and it is expected that it will support similar LTE sidelink CA features to NR (see RP-230077).

[0039] Dual Connectivity (DC) Dual connectivity is a feature first introduced in 4G LTE R12 that allows a UE to simultaneously connect to two cells located at different sites / base stations, enabling it to send and receive packets through both base stations. Both replication bearers (SRB, DRB) and split bearers can be configured for two cell groups (i.e., MCG and SCG) to improve reliability or throughput, respectively.

[0040] DC allows for looser coordination between cells. Cells can belong to different base stations, and may even belong to different radio access technologies, as in the case of NR-LTE dual connectivity in the case of Non-Standard Aron (NSA) operations. NSA operations were defined for the early deployment of NR in R15, where mobility and initial access-related control plane functions are performed over LTE, and user plane data transmission is performed over NR.

[0041] CA and DC can be combined. DC defines the terms "Master Cell Group (MCG)" and "Secondary Cell Group (SCG)," and CA can be used within each cell group. UEs supporting DC have different MAC entities for MCG and SCG, respectively.

[0042] Side link relay Sidelink relays were introduced in R17 to support the 5G ProSe UE-to-Network Relay (U2N Relay) function to provide network connectivity for U2N remote UEs, either within or outside network coverage (see WID RP-212819). A single unicast PC5 link is established between one U2N relay UE and one U2N remote UE.

[0043] Sidelink relay in R18 is further enhanced to support multi-route relay of U2N remote UEs within a base station's coverage, simultaneously establishing direct and indirect routes to the same base station via the U2N relay UE. Multi-route relay can be modeled similarly to DC in Layer 2 (including MAC, Radio Link Control (RLC), and Packet Data Translation Protocol (PDCP)), but the multi-route UE is assumed to have a single MAC entity when using resource allocation mode 1 for resource scheduling on the PC5 sidelink of the indirect route in the case of a DU.

[0044] Throughout this disclosure, only blocks, components, and / or devices related to the proposed embodiments are shown in the accompanying drawings. Other blocks are omitted for brevity. Furthermore, blocks designated by the same reference number are intended to have the same or at least similar functions, and therefore their functions are not described below.

[0045] Figure 1 illustrates the sidelink relay U2N relay function of 3GPP® 5G NR R17, where remote UEs 10 in out-of-coverage, in-coverage, and partial-coverage areas can be indirectly connected to base station 20 via relay UE 12. End-to-end SRB and DRB between remote UE 10 and base station 20 are transmitted via two hops: a PC5 hop between the remote UE and relay UE 12, and a Uu hop between relay UE 12 and base station 20.

[0046] Figure 2 illustrates the sidelink relay U2N relay multipath relay function of 3GPP® 5G NR R18, where a remote UE10 in the coverage simultaneously connects to base station 20 via both a direct path (DP) and an indirect path (IP). The direct path is on the Uu interface between the remote UE10 and base station 20, while the indirect path is the R17 sidelink relay U2N relay path via relay UE12.

[0047] Figure 3 illustrates the U2U sidelink relay function of 3GPP® 5G NR R18, where the source remote UE10-S connects indirectly to the target remote UE10-T via relay UE12 when a direct link between the source remote UE10-S and the target remote UE10-T is insufficient or impossible.

[0048] PDCP replication 5G NR PDCP replication is defined in R15 and enhanced in R16 to support RLC communication for Industrial IoT (IIoT) UEs. When replication is configured for a radio bearer by RLC, at least one secondary RLC entity is added to the radio bearer to handle the replicated PDCP PDUs (see TS38.300 V17.4.0, Section 16.1.3, Figures 16.1.3-1). All RLC entities have the same RLC mode. Therefore, replication in PDCP consists of submitting the same PDCP PDU multiple times, once to each activated RLC entity on the radio bearer. Having multiple independent transmission paths improves reliability and reduces latency through packet replication.

[0049] When replication is configured for an SRB, its state is always active and cannot be dynamically controlled.

[0050] When setting up replication for the DRB, the RRC also sets the PDCP replication status (activated or deactivated) at the time of (re)configuration. After configuration, the PDCP replication status can be dynamically controlled by the MAC control element (CE).

[0051] When replication is activated, the original PDCP PDU and its corresponding replication are not transmitted on the same carrier. Logical channels of a radio bearer configured with replication can belong to either the same MAC entity (called CA replication) or different MAC entities (called DC replication). CA replication can also be configured on one or both MAC entities along with DC replication when replication is configured on a radio bearer via three or more RLC entities. In CA replication, logical channel mapping restrictions are used within the MAC entity to prevent different logical channels of a radio bearer in the MAC entity from being transmitted on the same carrier. When CA replication is configured on an SRB, one of the logical channels associated with the SRB is mapped to a SpCell.

[0052] Figure 4 shows the PDCP replication scheme for 3GPP® 5G NR R15 using carrier aggregation. Here, the same PDCP data packet is transmitted by the PDCP entity 30 to the MAC entity 50 via a primary RLC entity (P-RLC) 42 and multiple secondary RLC entities (S-RLC) 44 through multiple RLC channels having different sequence numbers (SN=1, 2, 3…). On the transmitting side, each RLC channel / logical channel can be mapped to a different component carrier (CC1~CCn), and on the receiving side, the PDCP data packet is received via multiple RLC channels mapped to different component carriers, the replicated PDCP data packet is dropped by the receiving side, and only one copy of the PDCP service data unit (SDU) is sent to the upper layer.

[0053] Figure 5 shows a PDCP replication scheme for 3GPP® 5G NR R15 using dual connectivity. This differs from carrier aggregation-based PDCP replication schemes in that two cell groups are involved in dual connectivity, and Xn Application Protocol (XnAP) messages are defined to exchange PDCP data packets between the MCG and SCG via the Xn Interface (Xn-IF). On the transmission side, a PDCP entity 30 in the MCG sends a copy of the PDCP data packet to the SCG using XnAP messages, and both the MCG and SCG have their own RLC entities (primary RLC entity 42 in the MCG and secondary RLC entity 44 in the SCG) that can transmit the PDCP data packet using their own resources. On the receiving end, the same copy of the PDCP data packet is received by both the MCG and SCG. The SCG forwards the received PDCP data packet to the MCG using an XnAP message. The MCG detects the duplicate PDCP data, discards the duplicate, and sends only one copy of the PDCP SDU to the upper layer (i.e., MAC entity 50) using the respective carriers C1 and C2 of different cell groups (i.e., MCG and SCG).

[0054] Figure 6 shows a PDCP replication scheme in which both carrier aggregation and dual connectivity are applied. In either the MCG or SCG, PDCP data packets are sent to multiple component carriers CC. m_1 ~CC m_n or CC s_1 ~CC s_n The data packets are replicated via [a specific method], while between MCG and SCG, the PDCP data packets are replicated within each cell group.

[0055] Split Bearer In dual connectivity (DC), the UE is configured to utilize radio resources from two different gNBs: a master gNB (MgNB) that maintains the control plane and a secondary gNB (SgNB).

[0056] A split bearer is a bearer whose radio protocol is located in both the MgNB and SgNB in ​​order to use resources from both the MgNB and SgNB.

[0057] A non-split bearer is a bearer whose radio protocol is located in either the MgNB or SgNB in ​​order to use either the MgNB or SgNB resource, respectively.

[0058] According to TS38.323 V17.5.0, each radio bearer (RB) (except SRB0 on ​​the Uu interface) is associated with one PDCP entity. Each PDCP entity is associated with one, two, three, four, six, or eight RLC entities, depending on the RB characteristics (e.g., unidirectional / bidirectional, split / non-split) or RLC mode: - In the case of a split bearer, each PDCP entity is associated with two unacknowledged mode (UM) RLC entities (if in the same direction), four UM RLC entities (two in each direction), or two acknowledged mode (AM) RLC entities. - In the case of an RB configured using PDCP replication, each PDCP entity is associated with N UM RLC entities (in the same direction), 2 × N UM RLC entities (N in each direction), or N AM RLC entities (where 2 ≤ N ≤ 4). - In the case of a DAPS bearer, each PDCP entity is associated with two UM RLC entities (one in the source cell and one in the target cell if in the same direction), four UM RLC entities (two in each direction of the source and target cells), or two AM RLC entities (one in the source cell and one in the target cell). - In the case of UM Multicast / Broadcast Service (MBS)RB (MRB), each PDCP entity is associated with one UM RLC entity (for MBS traffic channels (MTCH) or downlink-only traffic channels (DTCH)), two UM RLC entities (one for MTCH and one for downlink DTCH, or one for downlink DTCH and one for uplink DTCH), or three UM RLC entities (one for MTCH, one for downlink DTCH, and one for uplink DTCH). - In the case of AM MRB, each PDCP entity is associated with one AM RLC entity (for downlink DTCH and uplink DTCH), or one UM RLC entity (for MTCH) and one AM RLC entity (for downlink DTCH and uplink DTCH). - Otherwise, each PDCP entity is associated with one UM RLC entity, two UM RLC entities (one in each direction), or one AM RLC entity.

[0059] Sidelink PDCP duplication 4G LTE supports sidelink carrier aggregation and sidelink PDCP replication in R15, improving reliability by allowing the same PDCP packets to be transmitted in parallel across multiple sidelink carriers. 4G LTE R15 supports sidelink PDCP replication across two different sidelink carriers. For details, please refer to TS36.323 V17.2.0 (2022~12), sections 5.1.3 and 5.1.4.

[0060] In 5G NR R18, 3GPP® has further enhanced sidelinks to support carrier aggregation, and it is expected that it will support similar LTE sidelink PDCP replication features to NR (see RP-230077).

[0061] Packet duplication / aggregation for sidelink relay As mentioned above, for sidelink relays (both U2N and U2U relays), there are existing mechanisms such as carrier aggregation, dual connectivity, and PDCP replication / aggregation for wireless links at each hop of the transmission path, such as sidelink CAs using PDCP / aggregation on PC5 links and Uu CAs using PDCP replication / aggregation on Uu links for U2N relays, and sidelink CAs using PDCP replication / aggregation on the first PC5 link between the source remote UE and the relay UE and the second PC5 link between the relay UE and the target remote UE for U2U relays. However, there is no packet replication / aggregation scheme that covers all wireless links at all hops of the end-to-end transmission path between the source node and the target node.

[0062] In multipath communication, an Access Traffic Steering Switching Splitting (ATSSS-enabled UE) capable of steering, switching, and splitting multi-access PDU session traffic across 3GPP® access and non-3GPP® access is called a "steering function" (TS23.501). An ATSSS-enabled UE can support one or more of the following types of steering functions: (1) high-layer steering functions that operate above the IP layer and can be based on multipath TCP or multipath QUIC; (2) low-layer steering functions that operate below the IP layer. For example, Figure 5.32.6.2.2~1 of TS23.501 illustrates the user plane protocol stack when the Multipath Quick User Datagram Protocol (UDP) Internet Connectivity (QUIC) function is applied between the UE and the UPF.

[0063] Figures 2 through 6 above schematically illustrate different multipath schemes that are known and / or supported by 3GPP® 5G / NR. However, there is no end-to-end SRB / DRB packet replication and / or data partitioning / aggregation scheme throughout all hops of the transmission path between the source node and the target node.

[0064] End-to-end packet replication Figure 7A schematically illustrates the end-to-end packet replication scheme between a remote UE and a base station in the case of an L2 U2N sidelink relay with two hops (i.e., PC5 and Uu) according to the first embodiment. At least one packet replication scheme is used at each hop. For example, the PC5 hop between the remote UE 10 and the relay UE 12 uses sidelink carrier aggregation (SL-C) to transmit packets (such as PDCP data packets) over multiple relay RLC channels on different sidelink component carriers. The Uu hop between the relay UE 12 and the base station 20 uses either carrier aggregation or dual connectivity, or both, to transmit replicated packets (such as PDCP data packets) over multiple relay RLC channels on different Uu component carriers or RLC channels within a cell group, or both. On the transmission side, user traffic is replicated at the PDCP layer, and PDCP data packets are replicated and transmitted over multiple relay RLC channels through all hops in the transmission path. On the receiving end, the receiving PDCP entity detects / discards duplicates and transmits only one copy of the PDCP SDU to the upper layer.

[0065] Because each hop employs a different packet replication scheme, and the number of relay RLC channels across all hops may vary from hop to hop, each node in the transmission path needs to maintain a table that maps end-to-end SRB / DRBs to relay RLC channels on each hop in the transmission path.

[0066] In one embodiment, the source node has an RLC bearer mapping table of multiple entries, where each entry has one end-to-end SRB / DRB mapping information to the corresponding relay RLC channel at the first hop of the transmission path. Furthermore, the source node has a parameter that determines whether to apply the packet replication scheme to multiple relay RLC channels.

[0067]

number

[0068] In the above Abstract Syntax Notation 1 (ASN.1) information element (IE) definitions, sl-SRAP-ConfigRemote contains the Sidelink Relay Adaptive Protocol (SRAP) configuration of the source node (remote UE10) as defined in TS38.351. sl-LocalIdentity indicates the local UE ID of the remote UE. pdcp-Duplication indicates whether PDCP replication is applied. sl-RemoteUE-RB-Identity indicates the end-to-end SRB / DRB identity of the data stream. sl-EgressRLC-Channel indicates a list of relay RLC channels for the corresponding end-to-end SRB / DRB on the first hop at the source node of the transmission path.

[0069] In a variation of the first embodiment, the relay node 12 has an RLC bearer mapping table of multiple entries, where each entry has mapping information for one end-to-end SRB / DRB to the corresponding relay RLC channels at the relay node of the transmission path, across two hops the relay node bridges. Furthermore, the relay node 12 has a parameter that determines whether to apply the packet replication scheme to the multiple relay RLC channels on either of the hops the relay node bridges.

[0070]

number

[0071] In the above ASN.1 IE definition, sl-LocalIdentity indicates the local UE ID of the remote UE, as defined in the SRAP protocol TS38.351. sl-RemoteUE-RB-Identity indicates the end-to-end SRB / DRB identity of the data stream. pdcp-DuplicationHop1 and pdcp-DuplicationHop2 indicate whether PDCP replication is applied on each hop the relay node bridges. sl-EgressRLC-ChannelHop1 and sl-EgressRLC-ChannelHop2 indicate a list of relay RLC channels for the corresponding end-to-end SRB / DRB on each hop the relay node bridges at the relay UE12 of the transmission path.

[0072] In a variation of the first embodiment, the target node (a RAN node such as a gNB, a gNB-DU / CU in the case of a U2N relay, or another remote UE in the case of a U2U relay) has an RLC bearer mapping table with multiple entries, where each entry has one end-to-end SRB / DRB mapping information to the corresponding relay RLC channel at the last hop of the transmission path. Furthermore, the target node has a parameter that determines whether to apply the packet replication scheme to multiple relay RLC channels.

[0073]

number

[0074] In the above ASN.1 IE definition, sl-SRAP-ConfigRemote contains the SRAP configuration for the target node (base station, gNB-DU / CU in L2 U2N relay, target remote UE in L2 U2U relay), as defined in TS38.351. sl-LocalIdentity indicates the local UE ID of the remote UE. sl-RemoteUE-RB-Identity indicates the end-to-end SRB / DRB identity of the data stream. pdcp-Duplication indicates whether PDCP replication is applied. sl-EgressRLC-Channel indicates a list of relay RLC channels for the corresponding end-to-end SRB / DRB on the last hop at the target node in the transmission path.

[0075] In a variation of the first embodiment, the relay RLC channel is a PC5 relay RLC channel mapped to a side link component carrier.

[0076] In a variation of the first embodiment, the relay RLC channel is bidirectional.

[0077] In a variation of the first embodiment, the target node is the base station gNB-DU / CU.

[0078] In a variation of the first embodiment, the target node is another remote UE.

[0079] In a variation of the first embodiment, the relay RLC channel is a Uu relay RLC channel mapped to the Uu component carrier of the MCG.

[0080] In a variation of the first embodiment, the relay RLC channel is a Uu relay RLC channel mapped to the Uu component carrier of the SCG.

[0081] In a variation of the first embodiment, the above configuration information includes the number of transmission paths (e.g., relay RLC channels) on each hop of the end-to-end transmission path.

[0082] In a variation of the first embodiment, the configuration information includes a default number of transmission paths (e.g., relay RLC channels) on each hop of an end-to-end transmission path specified by either a standard specification or network pre-configuration / SIB / RRC signaling.

[0083] In a variation of the first embodiment, the gNB and / or gNB-DU / CU configure configuration information related to end-to-end packet replication and / or data partitioning / aggregation (or a subset thereof) to one or more (potential) nodes (e.g., source device, target device, intermediate / relay device) when such nodes are within the base station's packet replication coverage.

[0084] In a variation of the first embodiment, configuration information related to end-to-end packet replication and / or data partitioning / aggregation (or a subset thereof) is pre-configured on the node (for example, through a set of policies provided by the network or installed on the device).

[0085] In a variation of the first embodiment, configuration information related to end-to-end packet replication and / or data partitioning / aggregation (or a subset thereof) is configured via RRC signaling, MAC control elements, and / or SIB broadcast and / or on-demand SIB requests.

[0086] In a variation of the first embodiment, configuration information related to end-to-end packet replication and / or data partitioning / aggregation (or a subset thereof) is configured on a node by receiving configuration information (or a subset thereof) from another node in the network (e.g., another node that is part of the transmission path), for example, by receiving a PC5-RRC or other message containing such configuration information via a side link from a node that has a direct link with the node.

[0087] In a variation of the first embodiment, the gNB and / or gNB-DU / CU may be information stored in the device's memory or storage, and therefore do not necessarily need to signal the configuration to itself.

[0088] In the first embodiment, user data is replicated according to the throughput and / or capacity of different relay RLC channels. Replication thresholds (e.g., minimum / maximum data volume, data rate, capacity, delay, jitter, reliability, transmit / receive error rate, or amount of lost frames) can be set / used to determine whether user traffic should be replicated on two or more RLC channels. Determining and / or applying thresholds further involves measuring the current performance of various connections and / or RLC channels (e.g., current data rate, signal strength, transmit / receive error rate, delays incurred, or amount of lost frames).

[0089] In another variation of the first embodiment, user traffic is replicated according to a desired data rate, desired reliability, desired error rate, or delay budget set by a QoS policy for the user traffic. Such a QoS policy is enforced by a higher layer in a Service Data Adaptive Protocol (SDAP) entity, which is responsible not only for mapping QoS flows from the 5G CN to the DRB, but also for marking QoS flow identifiers (QFIs) in uplink and downlink packets.

[0090] In another variation of the first embodiment, a node in the transmission path applies a QoS policy to other nodes in the transmission path.

[0091] In a third embodiment, Figure 8A schematically illustrates an end-to-end packet replication scheme between a source remote UE 10-S and a target remote UE 10-T in the case of an L2 U2U sidelink relay 12 with two hops (i.e., PC5 and PC5). At least one packet replication scheme is used at each hop. For example, the first PC5 hop between the source remote UE 10-S and the relay UE 12 uses sidelink carrier aggregation to transmit packets (such as PDCP data packets) over multiple RLC channels on different sidelink component carriers. Similarly, the second PC5 hop between the relay UE 12 and the target remote UE 10-T also uses sidelink carrier aggregation to transmit packets (such as PDCP data packets) over multiple RLC channels on different sidelink component carriers. On the transmission side, user traffic is replicated with PDCP entities, and PDCP data packets are replicated and transmitted over multiple relay RLC channels through all hops in the transmission path. On the receiving end, the receiving PDCP entity detects / discards duplicates and transmits only one copy of the PDCP SDU to the upper layer.

[0092] Because each hop employs a different packet replication scheme, and the number of alternative communication paths across all hops may vary from hop to hop, each node in the transmission path needs to maintain a table that maps end-to-end SRB / DRBs to relay RLC channels on each hop in the transmission path.

[0093] In a third embodiment, the source node (e.g., source node UE10-S) has an RLC bearer mapping table of multiple entries, where each entry has one end-to-end SRB / DRB mapping information to the corresponding relay RLC channel at the first hop of the transmission path. Furthermore, the source node (e.g., source node UE10-S) has a parameter that determines whether to apply the packet replication scheme to multiple relay RLC channels.

[0094] In a variation of the third embodiment, the relay node 12 has an RLC bearer mapping table of multiple entries, where each entry has one end-to-end SRB / DRB mapping information to the corresponding relay RLC channels of the two hops the relay node bridges at the relay node in the transmission path. Furthermore, the relay node 12 has a parameter that determines whether to apply the packet replication scheme to the multiple relay RLC channels on either of the hops the relay node bridges.

[0095] In a third embodiment, the target node (e.g., target node UE10-T) has an RLC bearer mapping table of multiple entries, where each entry has one end-to-end SRB / DRB mapping information to the corresponding relay RLC channel at the last hop of the transmission path. Furthermore, the target node (e.g., target node UE10-T) has a parameter that determines whether to apply the packet replication scheme to multiple relay RLC channels.

[0096] End-to-end data partitioning and aggregation Figure 7B shows an end-to-end data partitioning and aggregation scheme between a remote UE 10 and a base station 20 in the case of an L2 U2N sidelink relay, according to a second embodiment, in which there are two hops (i.e., PC5 and Uu). At least one data partitioning and aggregation scheme is used at each hop. For example, the PC5 hop between the remote UE 10 and the relay UE 12 uses sidelink carrier aggregation to transmit packets (such as PDCP data packets) over multiple relay RLC channels on different sidelink component carriers, with each relay RLC channel transmitting a portion of the packets according to a QoS policy configured for end-to-end user traffic, such as minimum / maximum data volume, data rate, capacity, delay, jitter, reliability, transmit / receive error rate, or amount of lost frames. The Uu hop between relay UE12 and base station 20 transmits segmented data packets (such as PDCP data packets) via multiple relay RLC channels mapped to different Uu component carriers, carriers within a cell group, or both, using either carrier aggregation or dual connectivity. On the transmitting side, user traffic is segmented at the PDCP layer, and PDCP data packets are transmitted via multiple relay RLC channels at every hop in the transmission path. On the receiving side, the receiving PDCP entity assembles the PDCP data packets received from the multiple relay RLCs in sequence and transmits the sequentially ordered PDCP SDU to the upper layer.

[0097] In a second embodiment, user traffic is segmented according to the throughput and / or capacity of different relay RLC channels. Data segmentation thresholds (e.g., minimum / maximum data volume, data rate, capacity, delay, jitter, reliability, transmit / receive error rate, or amount of lost frames) can be set / used to determine whether user traffic is transmitted over one relay RLC channel or over two or more relay RLC channels.

[0098] In the second embodiment, if the amount of data to be transmitted is below a threshold, user traffic is transmitted through only one relay RLC channel.

[0099] In the second embodiment, if the amount of data to be transmitted exceeds a threshold, user traffic is transmitted over multiple relay RLC channels.

[0100] In a variation of the second embodiment, user traffic is segmented according to the delay budget set by the QoS policy for the user traffic. The high-latency relay RLC channel carries the smaller portion of the user traffic, while the low-latency relay RLC channel carries the larger portion of the user traffic.

[0101] In a variation of the second embodiment, user traffic is divided according to a round-robin rule in which each relay RLC channel transmits the same amount of data.

[0102] In a variation of the second embodiment, the transmitting PDCP entity randomly selects only one relay RLC channel to transmit PDCP data packets carrying user traffic.

[0103] Because each hop employs a different data partitioning / aggregation scheme, and the number of relay RLC channels on all hops may vary from hop to hop, each node in the transmission path needs to maintain a table that maps end-to-end SRBs / DRBs to relay RLC channels on each hop in the transmission path.

[0104] In the second embodiment, the source node has an RLC bearer mapping table of multiple entries, where each entry has one end-to-end SRB / DRB mapping information to the corresponding relay RLC channel at the first hop of the transmission path. Furthermore, the source node has a threshold parameter that determines whether to apply data partitioning to multiple relay RLC channels.

[0105]

number

[0106] In the above ASN.1 IE definition, sl-SRAP-ConfigRemote contains the SRAP configuration for the source node (remote UE) as defined in TS38.351. sl-LocalIdentity indicates the local UE ID of the remote UE. sl-RemoteUE-RB-Identity indicates the end-to-end SRB / DRB identity of the data stream. sl-EgressRLC-Channel indicates a list of relay RLC channels for the corresponding end-to-end SRB / DRB on the first hop at the source node of the transmission path. ul-DataSplitThreashold indicates the threshold used to determine whether to apply data splitting to divide user traffic across multiple relay RLC channels.

[0107] In a variation of the second embodiment, the relay node 12 has an RLC bearer mapping table of multiple entries, where each entry has mapping information for one end-to-end SRB / DRB to the corresponding relay RLC channels of two adjacent hops that the relay node 12 bridges / interconnects in the transmission path. Furthermore, the relay node 12 has a threshold parameter for each of the two hops that the relay node bridges that determines whether to apply data partitioning to multiple relay RLC channels.

[0108]

number

[0109] In the above ASN.1 IE definition, sl-LocalIdentity indicates the local UE ID of the remote UE10, as defined in the SRAP protocol TS38.351. sl-RemoteUE-RB-Identity indicates the end-to-end SRB / DRB identity of the data stream. sl-EgressRLC-ChannelHop1 and sl-EgressRLC-ChannelHop2 indicate a list of relay RLC channels for the corresponding end-to-end SRB / DRB at each of the two adjacent hops of the relay UE12 in the transmission path. ul-DataSplitThreasholdHop1 and ul-DataSplitThreasholdHop2 indicate thresholds used to determine whether to apply data splitting to divide user traffic across multiple relay RLC channels at each of the two hops that the relay node bridges.

[0110] In a variation of the second embodiment, the target node has an RLC bearer mapping table of multiple entries, where each entry has one end-to-end SRB / DRB mapping information to the corresponding relay RLC channel at the last hop of the transmission path. Furthermore, the target node has a threshold parameter that determines whether to apply data partitioning to multiple relay RLC channels.

[0111]

number

[0112] In the above ASN.1 IE definition, sl-SRAP-ConfigRemote contains the SRAP configuration for the target node (base station in L2 U2N relay, target remote UE in L2 U2U relay), as defined in TS38.351. sl-LocalIdentity indicates the local UE ID of the remote UE. sl-RemoteUE-RB-Identity indicates the end-to-end SRB / DRB identity of the data stream. sl-EgressRLC-Channel indicates a list of relay RLC channels for the corresponding end-to-end SRB / DRB on the last hop at the target node of the transmission path. ul-DataSplitThreashold indicates the threshold used to determine whether to apply data splitting to divide user traffic across multiple relay RLC channels.

[0113] In a variation of the second embodiment, the relay RLC channel is a PC5 relay RLC channel transmitted over a sidelink component carrier.

[0114] In the variation of the second embodiment, the relay RLC channel is bidirectional. In the variation of the second embodiment, the target node is a base station.

[0115] In a variation of the second embodiment, the target node is a remote UE.

[0116] In a variation of the second embodiment, the relay RLC channel is a Uu relay RLC channel transmitted over the Uu component carrier of the MCG.

[0117] In a variation of the second embodiment, the relay RLC channel is a Uu relay RLC channel transmitted over the Uu component carrier of the SCG.

[0118] In a variation of the second embodiment, the gNB and / or gNB-DU / CU configure configuration information related to end-to-end packet replication and / or data partitioning / aggregation (or a subset thereof) to one or more (potential) nodes (e.g., source device, target device, intermediate / relay device) when such nodes are within the base station's packet replication coverage.

[0119] In a variation of the second embodiment, configuration information related to end-to-end packet replication and / or data partitioning / aggregation (or a subset thereof) is pre-configured on the node (for example, through a set of policies provided by the network or installed on the device).

[0120] In a variation of the second embodiment, configuration information related to end-to-end packet replication and / or data partitioning / aggregation (or a subset thereof) is configured via RRC signaling, MAC control elements, and / or SIB broadcast and / or on-demand SIB requests.

[0121] In a variation of the second embodiment, configuration information related to end-to-end packet replication and / or data partitioning / aggregation (or a subset thereof) is configured on a node by receiving configuration information (or a subset thereof) from another node in the network (e.g., another node that is part of the transmission path), for example, by receiving a PC5-RRC or other message containing such configuration information via a side link from a node that has a direct link with the node.

[0122] In a variation of the second embodiment, the gNB and / or gNB-DU / CU may be information stored in the device's memory or storage, and therefore do not necessarily need to signal the configuration to themselves.

[0123] In a second embodiment, user data is partitioned according to the throughput and / or capacity of different relay RLC channels. Data partitioning thresholds (e.g., minimum / maximum data volume, data rate, capacity, delay, jitter, reliability, transmit / receive error rate, or amount of lost frames) can be set / used to determine whether user traffic should be partitioned across two or more RLC channels. Determining and / or applying thresholds further involves measuring the current performance of various connections and / or RLC channels (e.g., current data rate, signal strength, transmit / receive error rate, delays incurred, or amount of lost frames).

[0124] In another variation of the second embodiment, user traffic is segmented according to a desired data rate, desired reliability, desired error rate, or delay budget set by a QoS policy for user traffic, and such QoS policies are applied by a higher layer in the SDAP entity.

[0125] In another variation of the second embodiment, a node in the transmission path applies a QoS policy to other nodes in the transmission path.

[0126] In a fourth embodiment, Figure 8B shows an end-to-end data splitting and aggregation scheme between a source remote UE 10-S and a target remote UE 10-T in the case of an L2 U2U sidelink relay 12 with two hops (i.e., PC5 and PC5). At each hop, some data splitting and aggregation scheme is used. For example, the first PC5 hop between the source remote UE 10-S and the relay UE 12 uses sidelink carrier aggregation to transmit split data (such as PDCP data packets) over multiple RLC channels on different sidelink component carriers. Similarly, the second PC5 hop between the relay UE 12 and the target remote UE 10-T also uses sidelink carrier aggregation to transmit split data (such as PDCP data packets) over multiple RLC channels on different sidelink component carriers. On the transmitting side, the split PDCP data packets are transmitted over multiple relay RLC channels at all hops in the transmission path. On the receiving end, the receiving PDCP entity assembles the received PDCP data packets in order and transmits only the PDCP SDUs in the correct order to the upper layer.

[0127] In a fourth embodiment, user traffic is partitioned according to the throughput and / or capacity of different relay RLC channels. Thresholds (also called data partitioning thresholds) are set / used to determine whether user traffic is transmitted over one relay RLC channel or two or more relay RLC channels. Determining and / or applying thresholds further involves measuring the current performance of various connections and / or RLC channels (e.g., current data rate, signal strength, transmit / receive error rate, delays incurred, or amount of lost frames).

[0128] In a variation of the fourth embodiment, user traffic is segmented according to the delay budget set by the QoS policy for the user traffic. The high-latency relay RLC channel carries the smaller portion of the user traffic, while the low-latency relay RLC channel carries the larger portion of the user traffic.

[0129] In a variation of the fourth embodiment, user traffic is divided according to a round-robin rule in which each relay RLC channel transmits the same amount of data.

[0130] In a variation of the fourth embodiment, the transmitting PDCP entity randomly selects only one relay RLC channel to transmit PDCP data packets carrying user traffic.

[0131] Because each hop employs a different data partitioning and aggregation scheme, and the number of alternative relay RLC channels on all hops may vary from hop to hop, each node in the transmission path needs to maintain a table that maps end-to-end SRB / DRBs to relay RLC channels on each hop in the transmission path.

[0132] In the fourth embodiment, the source node (e.g., source node UE10-S) has an RLC bearer mapping table of multiple entries, where each entry has one end-to-end SRB / DRB mapping information to the corresponding relay RLC channel at the first hop of the transmission path. Furthermore, the source node (e.g., source node UE10-S) has a threshold parameter that determines whether to apply data partitioning to multiple relay RLC channels.

[0133] In a variation of the fourth embodiment, the relay node 12 has an RLC bearer mapping table of multiple entries, where each entry has one end-to-end SRB / DRB mapping information to the corresponding relay RLC channels of the two hops the relay node bridges at the relay node 12 in the transmission path. Furthermore, the relay node 12 has a threshold parameter that determines whether to apply data partitioning to multiple relay RLC channels.

[0134] In the fourth embodiment, the target node (e.g., target node UE10-T) has an RLC bearer mapping table of multiple entries, where each entry has one end-to-end SRB / DRB mapping information to the corresponding relay RLC channel at the last hop of the transmission path. Furthermore, the target node (e.g., target node UE10-T) has a threshold parameter that determines whether to apply data partitioning to multiple relay RLC channels.

[0135] End-to-end packet transmission by implementing QoS policies on traffic flows In the first and / or second embodiments, Figure 9 schematically illustrates the transmission of packets from a source node 10 (e.g., a U2N remote UE) to a target node 20 (e.g., a gNB) by enforcing a QoS policy on the traffic flow, such as applying packet duplication and / or data splitting and aggregation at each hop, in the case of a U2N relay 12. This configuration is set by the pdcp-Duplication parameter to turn PDCP duplication on and / or off on hops and corresponding relay RLC channels, or by the ul-DataSplitThreshold parameter to split data traffic across multiple relay RLC channels at the transmitting end and assemble PDCP data packets at the receiving end.

[0136] At source node 10, the QoS flow is mapped to IP packets (IP-P), and then the radio bearer (RB) is mapped to the QoS flow. Next, a PC5 relay RLC channel is created and forwarded to U2N relay 12 via the PC5 sidelink radio bearer (PC5-SL-RB). At U2N relay 12, the PC5 relay RLC channel is mapped to a Uu relay RLC channel (Uu-RLC) and forwarded to target node 20 via the Uu radio bearer (Uu-RB). At target node 20, the QoS flow is mapped to the radio bearer, and the QoS flow is fed to the UPF, which maps IP packets to the QoS flow.

[0137] In the third and / or fourth embodiments, Figure 11 schematically illustrates the transmission of packets from a source node (e.g., source node UE10-S) to a target node (e.g., target node UE10-T) by enforcing a QoS policy on the traffic flow, such as applying packet duplication and / or data splitting and aggregation at each hop, in the case of a U2U relay 12. This configuration is set by the pdcp-Duplication parameter to turn PDCP duplication on and / or off on the hop and the corresponding relay RLC channel, or by the ul-DataSplitThreshold parameter to split the data traffic on the transmitting side into multiple relay RLC channels and assemble the PDCP data packets on the receiving side.

[0138] At source node 10-S, the QoS flow is mapped to IP packets (IP-P), and then the radio bearer (RB) is mapped to the QoS flow. Next, a PC5 relay RLC channel is created and forwarded to U2U relay 12 via the PC5 sidelink radio bearer (PC5-SL-RB). At U2U relay 12, the PC5 relay RLC input channel is mapped to the PC5 relay RLC output channel (Uu-RLC) and forwarded to target node 10-T via the PC5 sidelink radio bearer (PC5-SL-RB). At target node 10-T, the QoS flow is mapped to the radio bearer, and then the IP packets are mapped to the QoS flow.

[0139] In various embodiments, in a wireless network, a device (e.g., a UE, also called a source node, either within or outside network coverage) can communicate with another device (e.g., a base station, or another UE, also called a target node) via one or more relay nodes (e.g., relay UEs), and the transmission path between the source node and the target node consists of one or more hops. The method of communication between the source node and the target node is: A transmission path establishment step, wherein a source node initiates a discovery procedure to discover and select one or more relay nodes and establishes a transmission path to a target node. End-to-end packet replication and / or data partitioning and aggregation are configured at each hop in the transmission path, and each hop has multiple relay RLC channels, configuration step, A transmission step between a source node and a target node, wherein in the case of packet duplication, the same PDCP data packet is transmitted over multiple relay RLC channels, and in the case of data partitioning and aggregation, each partitioned PDCP data packet is transmitted over multiple relay RLC channels.

[0140] In the modified embodiment, an end-to-end transmission path is established by each node in the transmission path, immediately triggering the next connected node to establish a connection, and setting up packet replication and / or data partitioning and aggregation in a hop-by-hop scheme.

[0141] In the modified embodiment, the packet duplication and / or data partitioning and aggregation methods described above are enabled / disabled by RRC signaling.

[0142] In the modified embodiment, the packet replication and / or data partitioning and aggregation methods described above are enabled in accordance with QoS flow instructions for data traffic from the application layer.

[0143] In variations of the embodiment, the criteria for discovering, selecting, and re-selecting relay nodes include parameters such as whether the relay node supports packet replication and / or data partitioning and aggregation mechanisms on the bridge / interconnected hop.

[0144] In a variant embodiment, the relay node discovery message may include parameters indicating support for end-to-end packet replication and / or data partitioning and aggregation, which may directly or indirectly indicate this end-to-end support. The relay service code may function as such an (indirect) indication.

[0145] In a variant embodiment, the network broadcasts support for the proposed packet replication and data partitioning / aggregation scheme via SIB messages.

[0146] In a modified embodiment, the remote UE and relay UE can indicate their ability to support the proposed packet replication and data partitioning / aggregation scheme in the UE capability information message sent to the network during the initial network connection procedure.

[0147] In a modified embodiment, the packet replication mechanism at one hop of the transmission path is Uu carrier aggregation in PDCP replication.

[0148] In a modified embodiment, the packet replication mechanism at one hop of the transmission path is PC5 sidelink carrier aggregation with PDCP replication.

[0149] In a modified embodiment, the packet aggregation mechanism at one hop of the transmission path is Uu carrier aggregation in a split bearer.

[0150] In a modified embodiment, the packet aggregation mechanism at one hop of the transmission path is PC5 sidelink carrier aggregation in a split bearer.

[0151] In a modified embodiment, the packet aggregation mechanism at one hop of the transmission path is Uu dual connectivity.

[0152] In a modified embodiment, the packet aggregation mechanism at one hop of the transmission path is a non-3GPP® UE-UE link.

[0153] Figure 10 illustrates the protocol stack for end-to-end packet replication and / or data partitioning / aggregation of a sidelink relay U2N relay in the first and / or second embodiment. As can be seen from Figure 10, Uu-RRC, Uu-SDAP, and Uu-PDCP entities on the remote UE 10 and base station 20 communicate directly with each other, and the PC5 entity on the remote UE 10 communicates with the upper-layer Uu entity on base station 20 via relay UE 12 using the PC5-RLC interface and the Uu-RLC interface.

[0154] Figure 12 illustrates the protocol stack for end-to-end packet replication and / or data partitioning / aggregation of a sidelink relay U2U relay in a third and / or fourth embodiment. As can be seen from Figure 12, the RRC, SDAP, and PDCP entities of the source remote UE10-S and target remote UE10-T communicate directly with each other, and the PC5 entities of the source remote UE10-S communicate with the PC5 entities of the target remote UE10-T via relay UE12 using their respective PC5-RLC interfaces.

[0155] Figure 13 schematically illustrates an end-to-end packet replication and / or data partitioning / aggregation scheme of a sidelink relay, multihop relay, and U2N relay according to a fifth embodiment, where three consecutive relay UEs 12 are used between a remote UE 10 and a base station 20. The same principles described above in relation to the first and second embodiments apply here.

[0156] Figure 14 schematically illustrates the end-to-end packet replication and data partitioning / aggregation scheme of a sidelink relay, multihop relay, and U2U relay according to the sixth embodiment, where three consecutive relay UE12 are used between the source remote UE10-S and the target remote UE10-T. The same principles described above in relation to the third and fourth embodiments apply here.

[0157] In further embodiments, the packet replication and data partitioning / aggregation configuration involves configuring one or more hops in the transmission path to use packet replication (as described in relation to the first and third embodiments) and configuring the remaining hops in the transmission path to use data partitioning / aggregation (as described in relation to the second and fourth embodiments).

[0158] Figure 15 illustrates the protocol stack for an end-to-end packet replication and / or data partitioning / aggregation channel between a source remote UE10-S and a target remote UE10-T via two relay UE20s, according to the seventh embodiment. As can be seen from Figure 15, the PDCP entities of the source remote UE10-S and the target remote UE10-T communicate directly with each other, and their RLC entities are connected via the RLC entities of two consecutive relay UE20s.

[0159] Figure 16 illustrates potential deployment scenarios for various embodiments of the above embodiments. Here, a first relay device 1601 and a second relay device 1602 (such as two satellite relays) are used to relay the communication path between a source UE 1603 and a target UE 1604. Two communication links 1607 and 1608 are provided between the first relay device 1601 and the source UE 1603, and between the first relay device 1601 and the target UE 1604. Two further communication links 1609 and 1610 are provided between the second relay device 1602 and the source UE 1603, and between the second relay device 1602 and the target UE 1604. Furthermore, the scenario includes access devices (e.g., base stations and satellite gateways) 1605 of a radio access network and a core network 1606.

[0160] In the deployment scenario shown in Figure 16, the traffic exchanged between source UE1603 and target UE1604 is split and / or replicated via multipath connections, as described in relation to the embodiments above.

[0161] Figure 17 shows a protocol stack that enables traffic splitting / replication in at least some of the embodiments described above, using multipath TCP and / or multipath QUIC between a source UE 1701 and a target UE 1703 via at least one relay device 1702, which may be a UE-to-UE relay or another type of relay.

[0162] Here, source UE1701, relay device 1702, and target UE1703 are connected via a 5G access network (5G-AN) protocol layer (for 3GPP® access and non-3GPP® access), enabling communication between source UE1701 and target UE1703 over higher protocol layers such as Internet Protocol (IP), User Datagram Protocol (UDP), Multipath QUIC (MPQUIC) Transport Layer Security (TLS), Hypertext Transfer Protocol version 3 (HTTP / 3), and PDU.

[0163] In a variant embodiment relating to a UE-to-UE communication embodiment, the source UE and target UE establish a first path via a first relay, the source UE and target UE negotiate the addition of a second path via a second relay (instead of performing standard path switching), the source UE and target UE establish the second path, and the source UE and target UE establish a multipath link via the first and second relays.

[0164] In related embodiments, the source UE and target UE are connected through two IP address pairs, where one IP address pair corresponds to a first route and the second IP address pair corresponds to a second route, and the IP address pairs are used in combination with multi-route QUIC or multi-route TCP.

[0165] In related embodiment variations, a multipath QUIC connection between the source UE and the target UE encapsulates UDP packets exchanged between the source UE and the target UE.

[0166] In summary, this paper presents methods and systems for improving the reliability and throughput of relay devices, such as cellular relay devices used in side-link relay communications in cellular networks, as well as other relay devices such as access devices or satellites.

[0167] Although embodiments have been described in the context of 5G networks, their application is not limited to such types of networks. They can be applied to any type of wireless or cellular network that offers suitable options for end-to-end packet replication and / or data partitioning / aggregation across multiple hops.

[0168] Other variations of the disclosed embodiments will be understood and implementable by those skilled in the art in carrying out the claims, from the examination of the drawings, disclosures, and appended claims. In the claims, the word “equipped with” does not preclude other elements or steps, and singular elements do not preclude plural elements. A single processor or other unit may perform the functions of several items described in the claims. The mere fact that certain means are described in different dependent claims does not mean that combinations of these means cannot be used advantageously. The above description details certain embodiments. However, it will be understood that no matter how much the above description is detailed in the text, these embodiments can be carried out in many ways and are therefore not limited to the disclosed embodiments. Notwithstanding, the use of certain terms when describing certain features or aspects should not be construed as implying that the terms are redefined herein to be limited to including any particular features of the features or aspects to which they relate. Furthermore, the expression “at least one of A, B, and C” shall be understood as disjunctive, i.e., “A and / or B and / or C.”

[0169] A single unit or device can perform the functions of several items described in the claims. The mere fact that certain means are described in different dependent claims does not mean that combinations of these means cannot be used advantageously.

[0170] The operations described as shown in the embodiments above may be implemented as program code means of a computer program, and / or as dedicated hardware of an associated network device or function. The computer program may be stored and / or distributed on a suitable medium, such as a supplied optical storage medium or solid-state medium, together with or as part of other hardware, but may also be distributed in other forms, such as via the Internet or other wired or wireless communication systems.

Claims

1. A first communication device for a wireless network that supports end-to-end packet replication and / or data partitioning / aggregation across multiple hops, Establishing one or more communication paths between the first communication device and the second communication device, Receiving configuration information from another communication device within the wireless network, wherein the configuration information includes at least one parameter relating to the end-to-end packet replication and / or data partitioning / aggregation via one or more communication paths between the first communication device and the second communication device, and between the first communication device and at least one third communication device and / or between the at least one third communication device and the second communication device. Based on the aforementioned configuration information, one or more communication paths are established between the first communication device and the at least one third communication device, or Transmitting configuration information to the second communication device, including at least one parameter relating to the end-to-end packet replication and / or data partitioning / aggregation, via the one or more communication paths between the at least one third communication device and the second communication device, or To transmit and receive data between the first communication device and the at least one third communication device, and / or between the at least one third communication device and the second communication device, via one or more communication paths, by duplicating and / or dividing the data on one or more communication paths between the first communication device and the at least one third communication device, and / or between the at least one third communication device and the second communication device, and according to the configuration information. At least one of the above is performed based on the setting information. A first communication device adapted to perform the following:

2. The first communication device according to claim 1, wherein the one or more communication paths between the first communication device and the second communication device are one or more direct wireless connections or wireless link control RLC channels between the first communication device and the second communication device, and / or one or more indirect wireless connections or relay RLC channels between the first communication device and the second communication device via the at least one third communication device.

3. The first communication device according to claim 1 or 2, wherein the second communication device is not the destination endpoint of the transmitted duplicate / split data, nor is it the source of the received duplicate / split data.

4. The first communication device according to any one of claims 1 to 3, wherein the at least one parameter relating to the end-to-end packet replication over one or more communication paths includes a quality of service (QoS) policy and / or replication threshold.

5. The first communication device according to any one of claims 1 to 4, wherein the at least one parameter relating to the data partitioning / aggregation via the one or more communication paths includes a quality of service (QoS) policy and / or a data partitioning threshold.

6. A base station device in a wireless network that supports end-to-end packet replication and / or data partitioning / aggregation via a wireless link to one or more communication devices, If the base station device has a direct communication path to the first communication device, it connects directly to the first communication device. If the base station device has an indirect communication path to the first communication device via one or more second communication devices, it is indirectly connected to the first communication device. One or more communication paths are established between the first communication device and the base station device. A base station device adapted to configure the first communication device and the one or more second communication devices with at least one parameter relating to the end-to-end packet replication and / or data partitioning / aggregation via the one or more communication paths between the first communication device and the base station device, and / or between the first communication device or the base station device and the one or more second communication devices.

7. Based on the configuration information, establish one or more communication paths between the first communication device and one or more second communication devices, or Sending and receiving data via one or more communication paths between the first communication device, the base station device, and one or more second communication devices by duplicating and / or dividing the data on one or more communication paths between the first communication device, the base station device, and one or more second communication devices according to the configuration information. The base station device according to claim 6, further adapted to perform at least one of the above based on the configuration information.

8. A method for end-to-end packet replication and / or data partitioning / aggregation in a wireless network, The steps include establishing one or more communication paths between a first communication device and a second communication device, A step of receiving configuration information from another communication device in the wireless network, wherein the configuration information includes at least one parameter relating to the end-to-end packet replication and / or the data partitioning / aggregation via one or more communication paths between the first communication device and the second communication device, and between the first communication device and at least one third communication device and / or between the at least one third communication device and the second communication device. Based on the aforementioned configuration information, one or more communication paths are established between the first communication device and the at least one third communication device, or Transmitting configuration information to the second communication device, including at least one parameter relating to the end-to-end packet replication and / or data partitioning / aggregation, via the one or more communication paths between the at least one third communication device and the second communication device, or Sending and receiving data between the first communication device and the at least one third communication device, and / or between the at least one third communication device and the second communication device, via one or more communication paths, by duplicating and / or dividing the data on one or more communication paths between the first communication device and the at least one third communication device, and / or between the at least one third communication device and the second communication device, according to the configuration information. A step of performing at least one of the above based on the setting information, Methods that include...

9. A computer program that, when executed on a computer device, includes coding means for generating the steps of the method according to claim 8.

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