Method and apparatus for simultaneous transmission on multiple paths

Abstract

The invention relates to a method and device for simultaneous transmission on multiple paths. One embodiment of the present disclosure provides a relay user equipment (UE) comprising: a transceiver; and a processor coupled with the transceiver and configured to: receive configuration information associated with a data radio bearer (DRB) of a remote UE; and receiving, from at least one of a base station (BS) or the remote UE, a first indication indicating activation or deactivation of simultaneous transmissions on multiple paths of the DRB of the remote UE, wherein the multiple paths include at least one direct path and an indirect path.

Description

Technical Field

[0001] The present disclosure relates to wireless communication techniques, and more particularly, to methods and apparatus for simultaneous transmission over multiple paths. Background Art

[0002] Simultaneous transmissions on multiple paths can improve the performance of wireless networks. For example, by performing the same transmission on multiple paths, reliability is enhanced, and by performing different transmissions on multiple paths, throughput is improved.

[0003] Therefore, it is desirable to provide a solution for simultaneous transmission on multiple paths. Summary of the invention

[0004] One embodiment of the present disclosure provides a relay user equipment (UE), comprising: a transceiver; and a processor coupled to the transceiver and configured to: receive configuration information associated with a data radio bearer (DRB) of a remote UE; and receive a first indication of activation or deactivation of simultaneous transmission on multiple paths of the DRB of the remote UE from a base station (BS) or at least one of the remote UEs, wherein the multiple paths include at least one direct path and an indirect path.

[0005] In some embodiments, the first indication indicates at least one of: an identifier of a remote UE; an identifier of a DRB; an identifier of a path; an identifier of a radio link control (RLC); or an identifier of a logical channel.

[0006] In some embodiments, the first indication is associated with at least one of a DRB configured for the direct path or a DRB configured for the indirect path.

[0007] In some embodiments, the first indication includes at least one of: a radio resource control (RRC) message; an information element (IE) in an RRC message; downlink control information (DCI); a medium access control control element (MACCE); a control protocol data unit (PDU) of a sidelink relay adaptation protocol (SRAP) layer; or a control PDU of an RLC layer.

[0008] In some embodiments, the processor is further configured to: transmit the control PDU of the SRAP layer to the remote UE; or assemble, reassemble, generate or regenerate the control PDU of the SRAP layer, and transmit the assembled, reassembled, generated or regenerated control PDU of the SRAP layer to the remote UE.

[0009] In some embodiments, when the first indication includes the MAC CE or the control PDU of the RLC layer, the processor is further configured to: generate a second indication based on the first indication, wherein the second indication indicates activation or deactivation of simultaneous transmission on multiple paths of the DRB of the remote UE, and the second indication can be identified by the remote UE; and transmit the second indication to the remote UE via an interface between the remote UE and the relay UE.

[0010] In some embodiments, the processor is further configured to: transmit a response to the first indication, wherein the response includes at least one of: a confirmation of the activation or deactivation; a message; an acknowledgement (ACK); or a hybrid automatic repeat request acknowledgement (HARQ ACK); or wherein the response includes at least one of: a rejection of the activation or deactivation; a message; a negative acknowledgement (NACK); or a hybrid automatic repeat request negative acknowledgement (HARQ NACK).

[0011] Another embodiment of the present disclosure provides a remote UE, comprising: a transceiver; and a processor, which is coupled to the transceiver and configured to: receive configuration information associated with simultaneous transmission on multiple paths; and receive a first indication of activation or deactivation of simultaneous transmission on multiple paths of a DRB from at least one of a BS or a relay UE, wherein the multiple paths include at least one direct path and an indirect path.

[0012] In some embodiments, the first indication indicates at least one of: an identifier of a remote UE; an identifier of a DRB; an identifier of a path; an identifier of an RLC; or an identifier of a logical channel.

[0013] In some embodiments, the first indication comprises at least one of: a radio RRC message; an IE in an RRC message; a DCI; a MAC CE; a control PDU of a SRAP layer; or a control PDU of a RLC layer.

[0014] In some embodiments, the first indication is associated with at least one of a DRB configured for the direct path or a DRB configured for the indirect path.

[0015] In some embodiments, in the event that the first indication is received from the BS, the processor is further configured to: transmit a second indication to a relay UE indicating activation or deactivation of simultaneous transmission on multiple paths of the DRB.

[0016] In some embodiments, the processor is further configured to: receive a response to the second indication from the relay UE, wherein the response includes at least one of: a confirmation of the activation or deactivation; a message; an ACK; or a HARQ ACK; or wherein the response includes at least one of: a rejection of the activation or deactivation; a message; a NACK; or a HARQ NACK.

[0017] Another embodiment of the present disclosure provides a base station (BS), comprising: a transceiver; and a processor, which is coupled to the transceiver and configured to: transmit configuration information associated with a DRB of a remote UE; and transmit a first indication of activation or deactivation of simultaneous transmission on multiple paths of the DRB of the remote UE to at least one of the remote UE or the relay UE, wherein the multiple paths include at least one direct path and an indirect path.

[0018] In some embodiments, the first indication indicates at least one of: an identifier of a remote UE; an identifier of a DRB; an identifier of a path; an identifier of an RLC; or an identifier of a logical channel.

[0019] In some embodiments, the first indication comprises at least one of: a radio RRC message; an IE in an RRC message; a DCI; a MAC CE; a control PDU of a SRAP layer; or a control PDU of a RLB layer.

[0020] In some embodiments, the first indication is associated with at least one of a DRB configured for the direct path or a DRB configured for the indirect path.

[0021] In some embodiments, the processor is further configured to: perform the same transmission or different transmissions on the multiple paths to the remote UE.

[0022] Another embodiment of the present disclosure provides a method performed by a relay UE, comprising: receiving configuration information associated with a DRB of a remote UE; and receiving a first indication of activation or deactivation of simultaneous transmission on multiple paths of the DRB of the remote UE from a BS or at least one of the remote UEs, wherein the multiple paths include at least one direct path and an indirect path.

[0023] Another embodiment of the present disclosure provides a method performed by a remote UE, comprising: receiving configuration information associated with a DRB; and receiving a first indication of activation or deactivation of simultaneous transmission on multiple paths of the DRB from at least one of a BS or a relay UE, wherein the multiple paths include at least one direct path and an indirect path.

[0024] Another embodiment of the present disclosure provides a method performed by a BS, comprising: transmitting configuration information associated with a DRB of a remote UE; and transmitting a first indication of activation or deactivation of simultaneous transmission on multiple paths of the DRB of the remote UE to at least one of the remote UE or a relay UE, wherein the multiple paths include at least one direct path and an indirect path. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to describe the manner in which the advantages and features of the present application can be obtained, the description of the present application is presented by reference to specific embodiments of the present application illustrated in the accompanying drawings. These drawings depict only example embodiments of the present application and therefore should not be considered as limiting the scope thereof.

[0026] Figure 1 A schematic diagram illustrating a wireless communication system according to some embodiments of the present disclosure.

[0027] Figure 2 A user plane (UP) protocol stack for L2 UE to network relay according to some embodiments of the present disclosure is described.

[0028] Figure 3 A control plane (CP) protocol stack for L2 UE to network relay according to some embodiments of the present disclosure is described.

[0029] Figure 4 A method for simultaneous transmission on multiple paths performed by a relay UE according to some embodiments of the present disclosure is described.

[0030] Figure 5 A method for simultaneous transmission on multiple paths performed by a remote UE according to some embodiments of the present disclosure is described.

[0031] Figure 6 A method for simultaneous transmission on multiple paths performed by a BS according to some embodiments of the present disclosure is described.

[0032] Figure 7 A simplified block diagram illustrating an apparatus for simultaneous transmission on multiple paths in accordance with some embodiments of the present disclosure. DETAILED DESCRIPTION

[0033] The detailed description of the accompanying drawings is intended as a description of the currently preferred embodiments of the present invention and is not intended to represent the only form in which the present invention can be practiced. It should be understood that the same or equivalent functions can be accomplished by different embodiments that are intended to be included in the spirit and scope of the present invention.

[0034] Although the operations are depicted in a particular order in the figures, those skilled in the art will readily recognize that such operations need not be performed in the particular order shown or in sequential order or require all of the illustrated operations to be performed in order to achieve the desired result; sometimes, one or more operations may be skipped. In addition, the figures may schematically depict one or more example processes in the form of a flow chart. However, other operations not depicted may be incorporated into the schematically illustrated example processes. For example, one or more additional operations may be performed before, after, simultaneously with, or between any of the illustrated operations. In some cases, multitasking and parallel processing may be advantageous.

[0035] Reference will now be made in detail to some embodiments of the present disclosure, examples of which are illustrated in the accompanying drawings. To facilitate understanding, embodiments are provided under specific network architectures and new service scenarios, such as cellular telephone networks, networks based on time division multiple access (TDMA), networks based on code division multiple access (CDMA), networks based on orthogonal frequency division multiple access (OFDMA), LTE networks, networks based on the third generation partnership project (3GPP), LTE, advanced LTE (LTE-A), 3GPP 4G, 3GPP 5G NR, 3GPP Release 16 and above, satellite communication networks, high altitude platform networks, etc. The wireless communication system 100 may implement some other open or proprietary communication protocols, such as the IEEE 802.11 series, WiMAX, and other protocols. It is considered that all embodiments in the present disclosure are also suitable for similar technical problems as network architectures and new service scenarios develop; and in addition, the terms cited in the present disclosure may change, which should not affect the principles of the present disclosure.

[0036] Figure 1 A wireless communication system is depicted in accordance with some embodiments of the present disclosure.

[0037] refer to Figure 1 , the wireless communication system 100 may include at least one remote UE 101, at least one relay UE 103 and at least one BS 102. Figure 1 Only one remote UE 101, one BS 102, and one relay UE 103 are depicted in FIG. 1 , but it is contemplated that any number of remote UEs, relay UEs, and BSs may be included in the wireless communication system 100 .

[0038] In some embodiments of the present disclosure, remote UE 101 may be a device in different forms or with different capabilities. According to some embodiments of the present disclosure, remote UE 101 may include or may be referred to as a computing device, such as a desktop computer, a laptop computer, a personal digital assistant (PDA), a tablet computer, a smart TV (e.g., a TV connected to the Internet), a set-top box, a game console, a security system (including a security camera), a car computer, a network device (e.g., a router, a switch and a modem) or the like. According to some embodiments of the present disclosure, UE 101 may include or may be referred to as a portable wireless communication device, such as a smart phone, a cellular phone, a flip phone or any other device capable of sending and receiving information. In some embodiments, remote UE 101 may include or may be referred to as a wearable device, such as a smart watch, a fitness bracelet, an optical head-mounted display or the like. In addition, remote UE 101 may be referred to as a subscriber unit, a mobile device, a mobile station, a user, a terminal, a mobile terminal, a wireless terminal, a fixed terminal, a subscriber station, a user terminal or a device, or other terms used in the art are used to describe.

[0039] In some embodiments of the present disclosure, BS 102 may be referred to as an access point, an access terminal, a base, a base unit, a macro cell, a Node B, an enhanced Node B, an evolved Node B, a next generation Node B (gNB), a home Node B, a relay node or a device, or described using other terms used in the art. BS 102 is typically part of a radio access network that may include one or more controllers communicatively coupled to one or more corresponding BSs 102.

[0040] In some embodiments of the present disclosure, relay UE 103 may be a UE-to-network (U2N) relay UE. In some embodiments, relay UE may also be a UE-to-UE (U2U) relay UE. In some other embodiments, relay UE may be a U2N and U2U relay UE. Relay UE may receive data transmission from BS102 and forward the data transmission to UE 101 or identify data transmission from BS102 and (re)assemble or (re)generate data transmission, then transmit the (re)assembled or (re)generated data transmission to UE 101. Similarly, relay UE may receive data transmission from UE 101 and forward the data transmission to BS102 or identify data transmission from UE 101 and (re)assemble or (re)generate data transmission, then transmit the (re)assembled or (re)generated data transmission to BS102.

[0041] For data transmission between UE 101 and BS 102, there may be two paths. UE 101 and BS 102 may communicate via a direct path (i.e., Figure 1103) and DRB#2 may be configured to transmit on path#2. UE101 and BS102 may transmit data via an indirect path (i.e., a relay path) including UE 103. Figure 1 1) performs data transmission, and DRB #1 may be configured to transmit on path #1, and UE 101 is a remote UE of relay UE 103. An indirect path may be a type of UE-to-network transmission path, in which data is forwarded via a U2N relay UE between a U2N remote UE and a network. An indirect path may also be a type of UE-to-UE connection transmission path, in which data is forwarded via another UE. And the interface between the two UEs may be non-3GPP specified or 3GPP specified. The UE-to-UE connection may be ideal or non-ideal. For example, the UE-to-UE may be a smartphone and a smart watch. In addition, the two devices may belong to one person or different people.

[0042] To simplify the description, when UE 101 communicates via a direct path or an indirect path, the present disclosure refers to UE 101 as a remote UE. UE 101 may be a U2N remote UE, and may communicate with the network via a relay UE (e.g., relay UE 103). For example, UE 101 may use a Uu interface to perform data transmission with BS 102, and may use a PC5 interface to perform data transmission with relay UE 103. U2N relay UE may be a UE that provides functionality to support connection of a U2N remote UE to a network. For example, relay UE 103 may use a Uu interface to perform data transmission with BS 102, and may use a PC5 interface to perform data transmission with remote UE 101.

[0043] The remote UE 101 may perform simultaneous transmission on multiple paths, simultaneous transmission of DRBs, simultaneous transmission of logical channels, simultaneous transmission of RLC entities, simultaneous transmission of services, PDCP duplication, or packet duplication.

[0044] Hereinafter in the present disclosure, the expressions "simultaneous transmission on multiple paths", "simultaneous transmission of DRBs", "simultaneous transmission of logical channels", "simultaneous transmission of RLC entities", "simultaneous transmission of services", "PDCP duplication" or "packet duplication" may be used interchangeably where appropriate.

[0045] Figure 2 A user plane (UP) protocol stack for L2 UE to network relay according to some embodiments of the present disclosure is described.

[0046] It contains 3 components: Remote UE (e.g. Figure 1 Remote UE 101 in the relay UE (e.g. Figure 1 Relay UE103 in the UE) and BS (e.g. Figure 1 BS102 in). The user plane protocol stack of the remote UE may include Uu-SDAP, Uu-PDCP, PC5-SRAP, PC5-RLC, PC5-MAC and PC5-PHY. The user plane protocol stack of the relay UE may include PC5-SRAP, PC5-RLC, PC5-MAC, PC5-PHY, Uu-SRAP, Uu-RLC, Uu-MAC, Uu-PHY. The user plane protocol stack of the BS may include Uu-SDAP, Uu-PDCP, Uu-SRAP, Uu-RLC, Uu-MAC, Uu-PHY. The channel between the remote UE and the relay UE is a PC5 relay RLC channel, and the channel between the relay UE and the BS is a Uu relay RLC channel.

[0047] For both CP and UP at both PC5 and Uu interfaces, the SRAP sublayer is placed above the RLC sublayer. UuSDAP, PDCP and RRC terminate between L2 U2N remote UE and BS, while SRAP, RLC, MAC and PHY terminate in each hop (i.e., the link between L2U2N remote UE and L2 U2N relay UE and the link between L2U2N relay UE and BS).

[0048] For L2 U2N relaying, the SRAP sublayer on the PC5 hop is used only for bearer mapping purposes. There is no SRAP sublayer on the PC5 hop for relaying messages for L2 U2N remote UEs on BCCH and PCCH. There is no SRAP sublayer on the PC5 hop for messages for L2 U2N remote UEs on SRB0, but there is a SRAP sublayer on the Uu hop for both DL and UL.

[0049] Figure 3 A control plane protocol stack for L2 UE to network relay according to some embodiments of the present disclosure is described.

[0050] It contains 3 components: Remote UE (e.g. Figure 1 Remote UE 101 in the relay UE (e.g. Figure 1 Relay UE103 in the UE) and BS (e.g. Figure 1BS102 in). The control plane protocol stack of the remote UE may include Uu-RRC, Uu-PDCP, PC5-SRAP, PC5-RLC, PC5-MAC and PC5-PHY. The control plane protocol stack of the relay UE may include PC5-SRAP, PC5-RLC, PC5-MAC, PC5-PHY, Uu-SRAP, Uu-RLC, Uu-MAC, Uu-PHY. The control plane protocol stack of the BS may include Uu-RRC, Uu-PDCP, Uu-SRAP, Uu-RLC, Uu-MAC, Uu-PHY. The channel between the remote UE and the relay UE is a PC5 relay RLC channel, and the channel between the relay UE and the BS is a Uu relay RLC channel.

[0051] For L2 U2N relay, for uplink:

[0052] The Uu SRAP sublayer supports UL bearer mapping between the ingress PC5 relay RLC channel for relaying and the egress Uu relay RLC channel on the L2 U2N relay UE Uu interface. For uplink relay services, different end-to-end RBs (SRBs or DRBs) of the same remote UE and / or different remote UEs may be multiplexed on the same Uu relay RLC channel;

[0053] The Uu SRAP sublayer supports L2 U2N remote UE identification for UL traffic. The identity information of the L2 U2N remote UE Uu radio bearer and the local remote UE ID are included in the Uu SRAP header at UL for the BS to associate received packets of a specific PDCP entity associated with the correct Uu radio bearer of the remote UE;

[0054] The PC5 SRAP sublayer at the L2 U2N remote UE supports UL bearer mapping between remote UE Uu radio bearers and egress PC5 relay RLC channels.

[0055] For L2 U2N relay, for downlink:

[0056] The Uu SRAP sublayer supports DL bearer mapping at the BS to map the end-to-end radio bearers (e.g., SRBs or DRBs) of the remote UE into the Uu relay RLC channel on the relay UE Uu interface. The Uu SRAP sublayer supports DL bearer mapping and data multiplexing between multiple end-to-end radio bearers (SRBs or DRBs) of L2U2N remote UEs and / or different L2 U2N remote UEs and one Uu relay RLC channel on the relay UE Uu interface.

[0057] The Uu SRAP sublayer supports remote UE identification for DL ​​traffic. Identity information of the remote UE Uu radio bearer and the local remote UE ID are included by the BS at DL into the Uu SRAP header for the relay UE to map received packets from the remote UE Uu radio bearer to its associated PC5 relay RLC channel.

[0058] The PC5 SRAP sublayer at the relay UE supports DL bearer mapping between the ingress Uu relay RLC channel and the egress PC5 relay RLC channel;

[0059] The PC5 SRAP sublayer at the remote UE associates received packets for a specific PDCP entity associated with the correct Uu radio bearer of the remote UE based on the identity information contained in the Uu SRAP header.

[0060] The Local Remote UE ID is included in both the PC5 SRAP header and the Uu SRAP header. The L2 U2N relay UE is configured by the BS with the Local Remote UE ID to be used in the SRAP header. The remote UE obtains the Local Remote ID from the BS via Uu RRC messages including RRCSetup, RRCReconfiguration, RRCResume and RRCReestablishment. Uu DRBs and Uu SRBs are mapped to different PC5 relay RLC channels and Uu relay RLC channels in both the PC5 hop and the Uu hop.

[0061] It is the responsibility of the BS to avoid conflicts when using the Local Remote UE ID. The BS may update the Local Remote UE ID by sending the updated Local Remote ID to the relay UE via an RRCReconfiguration message. The serving BS may perform the Local Remote UE ID update independently of the PC5 unicast link L2 ID update procedure.

[0062] There may be some problems with multipath transmission via direct and indirect paths.

[0063] Problem 1: How to indicate activation or deactivation of simultaneous transmission on multiple paths to the relay UE.

[0064] In some cases, a relay UE (e.g., relay UE 103) may not know whether simultaneous transmission on multiple paths of a remote UE's DRB (e.g., DRB of UE 101) is activated. In this case, the relay UE may consider that simultaneous transmission on multiple paths of the remote UE's DRB is activated, and may monitor resources for related transmissions to avoid missing any potential reception. However, in the case where simultaneous transmission on multiple paths of the remote UE's DRB is not activated or is deactivated, the relay UE may still monitor resources, which may result in unnecessary power consumption.

[0065] Therefore, it is beneficial to indicate to the relay UE the activation or deactivation of simultaneous transmission on multiple paths of the remote UE's DRB.

[0066] Question 2: How to activate or deactivate simultaneous transmission on multiple paths of a remote UE.

[0067] Generally speaking, activation or deactivation can be achieved by activating or deactivating MAC CE. Signaling (ie, activating or deactivating MAC CE) can control the same side as the sender.

[0068] In a Rel-18 multipath scenario, a bearer may be assigned to a path. For example, a bearer (e.g., DRB#1) may be assigned to an indirect path (e.g., Figure 1 1), and another bearer (e.g., DRB#2) may be allocated to the direct path (i.e. Figure 1 Both DRB#1 and DRB#2 may be configured with simultaneous transmission on multiple paths. Simultaneous transmission on multiple paths of DRB#2 may be activated or deactivated by activating or deactivating MAC CE via the Uu interface between the BS and the remote UE. Figure 1 Simultaneous transmission on multiple paths of DRB#1 of path #1 in ), and there is no available MAC CE or signaling for activating or deactivating simultaneous transmission on multiple paths of DRB#1.

[0069] Therefore, it is advantageous to provide a solution to solve the above problems. It should be noted that the solution proposed in the present disclosure can be applied to any suitable wireless network, such as a wireless network including simultaneous transmission on multiple paths, wherein the transmission on the indirect path in the multiple paths is implemented via U2N relay UE, U2U relay UE or UE-to-UE connection transmission or the like. When UE-to-UE connection transmission is applied and the interface between UEs is not specified by 3GPP, the procedures on the PC5 interface mentioned in the present disclosure are implemented by the UE.

[0070] In the present disclosure, the UE capability may support transmission on multiple paths, or the UE capability may support transmission on multiple paths as a remote UE, or the UE capability may support simultaneous transmission on multiple paths, or the UE capability may support simultaneous transmission on multiple paths as a remote UE. The UE may report the UE capability to the BS or the network. Alternatively, the UE may be a specific type of UE, such as an R-18 UE or a Rel-18 remote UE or the like, and the BS may consider that this type of UE supports transmission on multiple paths, so the specific type of UE may not need to report the UE capability to the BS.

[0071] Solution 1:

[0072] Solution 1 aims to solve the problem of how to indicate activation or deactivation of simultaneous transmission on multiple paths to the relay UE.

[0073] Solution 1-1

[0074] In solution 1-1, the BS may transmit an indication to the relay UE to indicate activation or deactivation of configured simultaneous transmission on multiple paths of the DRB of the remote UE or to indicate that the configured simultaneous transmission on multiple paths of the DRB of the remote UE may be activated or deactivated after a duration. The length of the duration may be indicated in the indication or may be a fixed or preconfigured value.

[0075] The indication may be at least one of the following: an RRC message; an IE in an RRC message; RRC signaling; a MAC CE; a control PDU of the SRAP layer; a control PDU of the RLC layer; or a DCI carried by a PDCCH transmission.

[0076] The indication may indicate activation or deactivation of simultaneous transmission on multiple paths per remote UE per DRB. In other words, the indication may indicate activation or deactivation of simultaneous transmission on multiple paths for a specific remote UE and for a specific DRB. Thus, the indication may indicate one or more IDs of one or more remote UEs or one or more IDs of one or more DRBs, or both. For example, the indication may indicate: UE 101, DRB#1; the indication may indicate: UE A, DRB#2; or the indication may indicate: UE B, all configured DRBs, etc. In some other embodiments, the indication may also indicate one or more IDs of one or more paths, one or more IDs of one or more RLCs, one or more IDs of one or more LCHs, etc.

[0077] At the relay UE side, after receiving the indication, the relay UE may monitor potential transmissions of the remote UE, if the indication indicates activation of simultaneous transmissions on multiple paths of the remote UE's DRB, i.e., any potential transmissions from the remote UE to the BS via an indirect path and any potential transmissions from the BS to the remote UE via an indirect path.

[0078] In some other embodiments, after receiving an indication indicating activation of simultaneous transmission on multiple paths of the remote UE's DRB, the relay UE may determine whether simultaneous transmission on the indirect path of the remote UE's DRB is activated, because the activation of simultaneous transmission on multiple paths of the remote UE's DRB for the direct path may also be transmitted on the indirect path. When the relay UE determines that simultaneous transmission on the indirect path of the remote UE's DRB is activated, the relay UE may monitor the remote UE for potential transmissions.

[0079] In some embodiments, the relay UE may respond to the indication from the BS, and the response may be at least one of the following: confirmation of activation or deactivation; message (i.e., RRC message); ACK (i.e., RLC ACK or PDCP ACK); or HARQ ACK. Alternatively, the response may also be at least one of the following: rejection of activation or deactivation; message (i.e., RRC message); NACK (i.e., RLC NACK or PDCP NACK); or HARQ NACK.

[0080] In the case where the deactivation of simultaneous transmission on multiple paths of the DRB of the remote UE is indicated, the relay UE may determine whether the simultaneous transmission on the indirect path of the DRB of the remote UE is deactivated, because the deactivation of simultaneous transmission on multiple paths of the DRB of the remote UE for the direct path may be transmitted on the indirect path. When the relay UE determines that the simultaneous transmission on the indirect path of the DRB of the remote UE is deactivated, the relay UE may stop monitoring the resource pool used by the remote UE.

[0081] Alternatively, the BS may not transmit an indication to the relay UE and may configure or release resources on the PC5 interface. The configuration of resources on the PC5 interface may implicitly imply that simultaneous transmission on the indirect path of the remote UE's DRB is activated. The release of resources on the PC5 interface may implicitly imply that simultaneous transmission on the indirect path of the remote UE's DRB is deactivated.

[0082] Solution 1-2:

[0083] The BS or the relay UE may configure resources on the PC5 interface to the remote UE so that the remote UE can transmit necessary information. Alternatively, the BS may configure resources on the PC5 interface to the relay UE so that the relay UE can transmit necessary information.

[0084] At the remote UE side, it may receive a first indication from the BS, which may indicate activation or deactivation of simultaneous transmission on multiple paths per DRB. That is, the first indication may include one or more IDs of one or more DRBs, such as: DRB#1, DRB#2, etc. In some other cases, the first indication may also include one or more IDs of one or more paths, one or more IDs of one or more RLCs, one or more IDs of one or more LCHs, etc. The first indication may be at least one of the following: an RRC message; an IE in an RRC message; RRC signaling; a MAC CE; a control PDU of the SRAP layer; a control PDU of the RLC layer; or a DCI carried on a PDCCH transmission.

[0085] Based on the first indication, the remote UE may transmit a second indication to the relay UE, and the second indication may indicate one of the following:

[0086] a) activation or deactivation of configured simultaneous transmission on multiple paths of DRBs of remote UEs or activation or deactivation of configured simultaneous transmission on which path or activation or deactivation of configured simultaneous transmission on which path of DRBs of remote UEs;

[0087] b) the configured simultaneous transmission on multiple paths of the remote UE's DRB may be activated or deactivated after a duration or the activation or deactivation of the configured simultaneous transmission on which path after a duration or the activation or deactivation of the configured simultaneous transmission on which path of the remote UE's DRB after a duration;

[0088] c) a request for activation or deactivation of simultaneous transmission on multiple paths of a remote UE's DRB or a request for which path to activate or deactivate simultaneous transmission or a request for which path to activate or deactivate simultaneous transmission of a remote UE's DRB; or

[0089] d) A request for activation or deactivation of simultaneous transmission on multiple paths of the DRB of the remote UE after the duration or a request for activation or deactivation of simultaneous transmission on which path after the duration or a request for activation or deactivation of simultaneous transmission on which path of the DRB of the remote UE after the duration.

[0090] The length of the duration may be indicated in the second indication, or may be a fixed or preconfigured value.

[0091] The second indication may include one or more IDs corresponding to one or more DRBs that are activated or deactivated and transmitted simultaneously on multiple paths, such as DRB #1, DRB #2, etc. In some other cases, the second indication may also include one or more IDs of one or more paths, one or more IDs of one or more RLCs, one or more IDs of one or more LCHs, etc.

[0092] In some embodiments, the relay UE may respond to the second indication from the remote UE, and the response may be at least one of the following: confirmation of activation or deactivation; message (i.e., RRC message); ACK (i.e., RLC ACK or PDCP ACK); or HARQ ACK. Alternatively, the response may also be at least one of the following: rejection of activation or deactivation; message (i.e., RRC message); NACK (i.e., RLC NACK or PDCP NACK); or HARQ NACK.

[0093] Solution 2:

[0094] Solution 2 aims to solve the problem of how to activate or deactivate simultaneous transmission on multiple paths of a remote UE.

[0095] Solution 2-1

[0096] The present disclosure proposes that activation or deactivation of simultaneous transmission on multiple paths corresponding to DRBs configured on the paths may be indicated by an indication transmitted via any path. For example, activation or deactivation of simultaneous transmission on multiple paths corresponding to DRBs configured on path #1 may be indicated by an indication transmitted via any one of path #1, path #2, path #3, etc.

[0097] In some other embodiments, activation or deactivation of simultaneous transmission on multiple paths corresponding to DRBs configured on indirect paths may be indicated by an indication transmitted via a direct path, and activation or deactivation of simultaneous transmission on multiple paths corresponding to DRBs configured on direct paths may not be indicated by an indication transmitted via an indirect path. That is, activation or deactivation of simultaneous transmission on multiple paths corresponding to DRBs configured on any path (including both direct and indirect paths) may only be indicated by an indication transmitted via a direct path.

[0098] In some other embodiments, activation or deactivation of simultaneous transmission on multiple paths corresponding to DRBs configured on direct paths may be indicated by an indication transmitted via an indirect path, and activation or deactivation of simultaneous transmission on multiple paths corresponding to DRBs configured on indirect paths may not be indicated by an indication transmitted via a direct path. That is, activation or deactivation of simultaneous transmission on multiple paths corresponding to DRBs configured on any path (including both direct and indirect paths) may only be indicated by an indication transmitted via an indirect path.

[0099] Hereinafter in this disclosure, a direct path may be one of the direct paths (when more than one direct path is configured), and an indirect path may be one of the indirect paths (when more than one indirect path is configured).

[0100] In some embodiments, activation or deactivation of simultaneous transmission on multiple paths corresponding to DRBs configured on the paths may be indicated by indications transmitted via two or more paths, and the two or more paths may be any two or more paths among the multiple paths.

[0101] The BS may ensure that the ID of the DRB is not repeatedly configured on different paths. For example, activation or deactivation of simultaneous transmission on multiple paths corresponding to DRB #1, DRB #2, and DRB #3 may be indicated by an indication transmitted via path #1, and activation or deactivation of simultaneous transmission on multiple paths corresponding to DRB #4, DRB #5, and DRB #6 may be indicated by an indication transmitted via path #2. For example, the BS may ensure that DRB #1 is only configured on path #1, not on path #2.

[0102] The indication may indicate at least one of the following: an RRC message; an IE in an RRC message; a DCI; a MAC CE; a PDU of an SRAP layer; or a control PDU of an RLC layer. The indication may indicate at least one of the following: one or more identifiers of one or more remote UEs; one or more identifiers of a DRB; one or more identifiers of one or more paths; one or more identifiers of one or more RLCs; or one or more identifiers of one or more logical channels.

[0103] Solution 2-2

[0104] The present disclosure proposes to introduce a new indication, such as a new MAC CE or a new LCID, which may indicate which path, which RLC, or which logical channel one or more DRBs correspond to. For example, the indication may indicate that: DRB#1 and DRB#2 correspond to path#1; and DRB#3 and DRB#4 correspond to path#2. The MAC CE may indicate at least one of the following: one or more IDs of one or more DRBs, one or more IDs of one or more paths, one or more IDs of one or more RLCs; or one or more IDs of one or more logical channels. The indication may also indicate one or more IDs of one or more remote UEs.

[0105] The new MAC CE or the new LCID may be transmitted via any path, such as path #1, path #2, direct path, indirect path, etc. Alternatively, the new MAC CE or the new LCID may be transmitted via only one of the direct paths. Alternatively, the new MAC CE or the new LCID may be transmitted via only one of the indirect paths.

[0106] The BS may transmit a new MAC CE or a new LCID to a remote UE via a Uu interface, and the remote UE knows which path the DRB indicated by the MAC CE corresponds to. The BS may also transmit a new MAC CE or a new LCID to a relay UE via a Uu interface, and the relay UE knows which path the DRB indicated by the MAC CE corresponds to. The BS may also transmit a new MAC CE or a new LCID to a remote UE via an indirect path, and the relay UE may transmit a new MAC CE or a new LCID to the remote UE.

[0107] Regarding the transmission of MAC CE via an indirect path, the detailed transmission method is described in the following solution 2-4.

[0108] Solution 2-3

[0109] In this solution, it is proposed that the control PDU in the SRAP layer can be used to indicate: 1) activation or deactivation of simultaneous transmission on multiple paths of DRBs of the remote UE; and 2) identifiers of DRBs associated with the paths (including direct paths, indirect paths, or any paths).

[0110] Specifically, the RRC layer of the BS may trigger or may instruct the control PDU of the SRAP layer to generate the control PDU of the SRAP layer. The BS may then transmit the control PDU of the SRAP layer to the relay UE via the Uu interface.

[0111] At the relay UE side, the relay UE may identify the control PDU of the SRAP layer, for example, identify the identifier of the DRB, identify the activation or deactivation state, etc. The relay UE may assemble, reassemble, generate, or regenerate the control PDU of the SRAP layer and transmit the assembled or reassembled, generated, or regenerated control PDU of the SRAP layer to the remote UE via the PC5 interface. In the present disclosure, the expressions "assemble", "reassemble", "generate", or "regenerate" may be used interchangeably where appropriate, and the expressions "assembled", "reassembled", "generated", or "regenerated" may be used interchangeably where appropriate.

[0112] Alternatively, the relay UE may forward the control PDUs of the SRAP layer to the remote UE via the PC5 interface.

[0113] In some other embodiments, the control PDU in the SRAP layer may further indicate at least one of the following: one or more IDs of one or more remote UEs, one or more IDs of one or more DRBs, one or more IDs of one or more paths, one or more IDs of one or more RLCs; or one or more IDs of one or more logical channels.

[0114] Solutions 2-4

[0115] The MAC layer or the RLC layer of the relay UE may receive a first indication of activation or deactivation of simultaneous transmission on multiple paths of the DRB of the remote UE from the BS. The first indication of activation or deactivation of simultaneous transmission on multiple paths of the DRB of the remote UE may be a type of MAC CE, such as an existing MAC CE or a new MAC CE. The MAC layer of the relay UE may receive the MAC CE from the BS. Alternatively, the first indication may be a new RLC control PDU or the like. The first indication may be an RLC control PDU, and the RLC layer of the relay UE may receive the RLC control PDU from the BS.

[0116] The first indication may indicate: an ID of a remote UE and a corresponding ID of a DRB. The ID of a remote UE and a corresponding ID of a DRB may be assembled with the first indication. In some embodiments, the first indication may further indicate at least one of: one or more IDs of one or more remote UEs, one or more IDs of one or more DRBs, one or more IDs of one or more paths, one or more IDs of one or more RLCs; or one or more IDs of one or more logical channels.

[0117] After receiving the first indication, the relay UE may generate a second indication based on the first indication. The second indication may be identifiable by the remote UE. The second indication may indicate the activation or deactivation of simultaneous transmission on multiple paths of the DRB of the remote UE. The relay UE may transmit the second indication to the remote UE via the PC5 interface. The second indication may be a MAC CE or an RLC control PDU. In some embodiments, the second indication may further indicate at least one of the following: one or more IDs of one or more remote UEs, one or more IDs of one or more DRBs, one or more IDs of one or more paths, one or more IDs of one or more RLCs; or one or more IDs of one or more logical channels.

[0118] The second indication may be generated in the following manner: after receiving the first indication (e.g., Uu MAC CE (or Uu RLC control PDU)) via the Uu interface, the Uu-MAC (or Uu-RLC) of the relay UE may transmit the information contained in the Uu MAC CE (e.g., the ID of the remote UE and the ID of the DRB) to the Uu-SRAP of the relay UE, and the Uu-SRAP of the relay UE may transmit the information to the PC5-SRAP. Then, the PC5 MAC CE or PC5 RLC control PDU may be generated by the PC5-PHY and transmitted to the remote UE via the PC5 interface. In this way, the information contained in the Uu MAC CE (or Uu RLC control PDU) from the BS is transmitted on an indirect path.

[0119] Solutions 2-5

[0120] In this solution, it is proposed that the BS can configure all duplicate DRBs to the direct path. Figure 1 Path #2 in .

[0121] Figure 4 A method for wireless communication performed by a relay UE according to some embodiments of the present disclosure is described.

[0122] In operation 401, the relay UE may receive configuration information associated with a DRB of a remote UE. In operation 402, the relay UE may receive a first indication indicating activation or deactivation of simultaneous transmission on multiple paths of the DRB of the remote UE from at least one of the BS or the remote UE, wherein the multiple paths include at least one direct path and an indirect path.

[0123] In some embodiments, the first indication may indicate at least one of the following:

[0124] The remote UE identifier, for example, the remote UE ID may be Figure 1 Remote 101 shown in;

[0125] The identifier of a DRB. For example, the ID of a DRB may be DRB#1, DRB#2, DRB#3, etc.

[0126] The identifier of the path. For example, the path ID can be Figure 1 Path #1, Path #2, or other ID of the path shown in;

[0127] The identifier of the RLC; or

[0128] Identifier of the logical channel.

[0129] In some embodiments, the first indication is associated with a DRB configured for a direct path, a DRB configured for an indirect path, or both. For example, the first indication may be associated with DRB#1 configured for an indirect path, DRB#2 configured for a direct path, or both DRB#1 configured for an indirect path and DRB#2 configured for a direct path.

[0130] In some embodiments, the first indication includes at least one of the following:

[0131] RRC message;

[0132] IE in RRC message;

[0133] DCI;

[0134] MAC CE;

[0135] SRAP layer control PDU; or

[0136] Control PDU of the RLC layer.

[0137] In some embodiments, the relay UE may: transmit the control PDU of the SRAP layer to the remote UE; or assemble, reassemble, generate or regenerate the control PDU of the SRAP layer, and transmit the assembled, reassembled, generated or regenerated control PDU of the SRAP layer to the remote UE.

[0138] In some embodiments, in the case where the first indication includes a control PDU of a MAC CE or an RLC layer, the relay UE may: generate a second indication based on the first indication, wherein the second indication indicates activation or deactivation of simultaneous transmission on multiple paths of the remote UE's DRB, and the second indication can be identified by the remote UE; and transmit the second indication to the remote UE via an interface between the remote UE and the relay UE. For example, in solution 2-4, the MAC layer or RLC of the relay UE may receive the first indication, which is transmitted via the Uu interface between the BS and the relay UE and cannot be identified by the remote UE. The relay UE may generate a second indication that can be identified by the remote UE and indicates activation or deactivation of simultaneous transmission on multiple paths of the remote UE's DRB and transmit the second indication to the remote UE.

[0139] In some embodiments, the relay UE may transmit a response to the first indication, wherein the response includes at least one of: confirmation of activation or deactivation; a message; an ACK; or a HARQ ACK; or wherein the response includes at least one of: a rejection of activation or deactivation; a message; a NACK; or a HARQ NACK.

[0140] Figure 5 A method for simultaneous transmission on multiple paths performed by a remote UE according to some embodiments of the present disclosure is described.

[0141] In operation 501, the remote UE may receive configuration information associated with simultaneous transmission on multiple paths. In operation 502, the remote UE may receive a first indication indicating activation or deactivation of simultaneous transmission on multiple paths of a DRB from at least one of a BS or a relay UE, wherein the multiple paths include at least one direct path and an indirect path.

[0142] In some embodiments, in the case where the first indication is received from the BS, the remote UE may transmit a second indication indicating activation or deactivation of simultaneous transmission on multiple paths of the DRB to the relay UE. For example, in solution 1-2, the remote UE may transmit an indication indicating activation or deactivation of configured simultaneous transmission on multiple paths of the DRB of the remote UE or activation or deactivation of configured simultaneous transmission on which path or activation or deactivation of configured simultaneous transmission on which path of the DRB of the remote UE, as described in item (a).

[0143] Figure 6 A method for simultaneous transmission on multiple paths performed by a BS according to some embodiments of the present disclosure is described.

[0144] In operation 601, the BS may transmit configuration information associated with a DRB of a remote UE. In operation 602, the BS may transmit a first indication indicating activation or deactivation of simultaneous transmission on multiple paths of the DRB of the remote UE to at least one of the remote UE or the relay UE, wherein the multiple paths include at least one direct path and an indirect path.

[0145] In some embodiments, the BS may perform the same transmission or different transmissions on multiple paths to the remote UE.

[0146] Figure 7 A simplified block diagram illustrating an apparatus for simultaneous transmission on multiple paths in accordance with some embodiments of the present disclosure.

[0147] like Figure 7 , an example of an apparatus 700 may include at least one processor 704 and at least one transceiver 702 coupled to the processor 704. The apparatus 700 may be a UE, a remote UE, a relay UE, a U2N relay UE, a U2U relay UE, a U2N and U2U relay UE, a BS, a RAN node, a source node, a target node, a third node, or any other device having similar functionality.

[0148] Although in this figure, elements are described in singular form, such as at least one transceiver 702 and processor 704, plural form is contemplated unless limitation to the singular form is explicitly stated. In some embodiments of the present disclosure, transceiver 702 may be divided into two devices, such as a receiving circuit system and a transmitting circuit system. In some embodiments of the present disclosure, device 700 may further include an input device, a memory and / or other components.

[0149] In some embodiments of the present disclosure, the device 700 may be a UE. The transceiver 702 and the processor 704 may interact with each other to perform Figures 1 to 6 In some embodiments of the present disclosure, the device 700 may be a node. The transceiver 702 and the processor 704 may interact with each other to perform Figures 1 to 6 The operation of a node described in any of .

[0150] In some embodiments of the present disclosure, the apparatus 700 may further include at least one non-transitory computer-readable medium.

[0151] For example, in some embodiments of the present disclosure, a non-transitory computer-readable medium may store computer-executable instructions to enable the processor 704 to implement the method described above with respect to the UE. For example, when the computer-executable instructions are executed, the processor 704 interacts with the transceiver 702 to perform Figures 1 to 6 Operation of the UE described in any one of .

[0152] In some embodiments of the present disclosure, a non-transitory computer-readable medium may store computer-executable instructions to enable the processor 704 to implement the node method described above. For example, when the computer-executable instructions are executed, the processor 704 interacts with the transceiver 702 to perform Figures 1 to 6 The operation of a node described in any of .

[0153] The methods of the present disclosure may be implemented on a programmed processor. However, the controller, flow charts, and modules may also be implemented on a general or special purpose computer, a programmed microprocessor or microcontroller and peripheral integrated circuit components, an integrated circuit, a hardware electronic or logic circuit (e.g., a discrete component circuit), a programmable logic device, or the like. In general, any device having a finite state machine capable of implementing the flow charts shown in the figures may be used to implement the processing functions of the present disclosure.

[0154] Although the present disclosure has been described using specific embodiments of the present disclosure, it is apparent that many alternatives, modifications, and variations will be apparent to those skilled in the art. For example, the various components of the embodiments may be interchangeable, added, or substituted in other embodiments. Moreover, all of the elements shown in each figure are not necessary for the operation of the disclosed embodiments. For example, a person skilled in the art of the disclosed embodiments will be able to make and use the teachings of the present disclosure by simply adopting the elements of the independent claims. Therefore, the embodiments of the present disclosure set forth herein are intended to be illustrative rather than restrictive. Various changes may be made without departing from the spirit and scope of the present disclosure.

[0155] In the present disclosure, for example, the relational terms of "first", "second" and the like can be used alone to distinguish one entity or action from another entity or action, without necessarily requiring or implying any actual such relationship or order between such entities or actions. The term "comprises, comprising" or any other variation thereof is intended to cover non-exclusive inclusion, so that the process, method, article or equipment including a series of elements not only includes those elements but also may include other elements that are not explicitly listed or inherent to this process, method, article or equipment. The elements starting with "a, an" or the like do not exclude the presence of additional identical elements in the process, method, article or equipment including the elements without more constraints. Moreover, the term "another" is defined as at least the second or more. As used herein, the terms "include", "have" and the like are defined as "include".

Claims

1. A relay user equipment UE, comprising: Transceiver; and a processor coupled to the transceiver and configured to: receiving configuration information associated with a data radio bearer (DRB) of a remote UE; and A first indication indicating activation or deactivation of simultaneous transmission on multiple paths of the DRB for the remote UE is received from at least one of a base station BS or the remote UE, wherein the multiple paths include at least one direct path and an indirect path.

2. The relay UE according to claim 1, wherein the first indication indicates at least one of the following: An identifier of the remote UE; The identifier of the DRB; The identifier of the path; an identifier of a radio link control, RLC; or Identifier of the logical channel. 3 . The relay UE according to claim 1 , wherein the first indication is associated with at least one of a DRB configured for the direct path or a DRB configured for the indirect path.

4. The relay UE according to claim 1, wherein the first indication comprises at least one of the following: Radio Resource Control RRC messages; Information element IE in RRC message; Downlink control information DCI; Media Access Control Element MAC CE; Control protocol data unit PDU of the side link relay adaptation protocol SRAP layer; or Control PDU of the RLC layer.

5. The relay UE according to claim 4, wherein the processor is further configured to: transmitting the control PDU of the SRAP layer to the remote UE; or The control PDUs of the SRAP layer are assembled or reassembled, and the assembled or reassembled control PDUs of the SRAP layer are transmitted to the remote UE.

6. The relay UE according to claim 4, wherein in a case where the first indication includes the MAC CE or the control PDU of the RLC layer, the processor is further configured to: generating a second indication based on the first indication, wherein the second indication indicates activation or deactivation of simultaneous transmission on multiple paths of the DRB of the remote UE, and the second indication is recognizable by the remote UE; and The second indication is transmitted to the remote UE via an interface between the remote UE and the relay UE.

7. The relay UE according to claim 1, wherein the processor is further configured to: transmitting a response to the first indication, wherein the response comprises at least one of: a confirmation of the activation or deactivation; a message; an acknowledgement ACK; or a hybrid automatic repeat request acknowledgement HARQ ACK; or The response comprises at least one of: a rejection of the activation or deactivation; a message; a negative acknowledgement (NACK); or a hybrid automatic repeat request negative acknowledgement (HARQ) (NACK).

8. A remote user equipment UE, comprising: Transceiver; and a processor coupled to the transceiver and configured to: receiving configuration information associated with simultaneous transmission on multiple paths; and A first indication indicating activation or deactivation of simultaneous transmission on multiple paths of a data radio bearer (DRB) is received from at least one of a base station (BS) or a relay (UE), wherein the multiple paths include at least one direct path and an indirect path.

9. The remote UE of claim 8, wherein the first indication indicates at least one of: An identifier of the remote UE; The identifier of the DRB; The identifier of the path; an identifier of a radio link control, RLC; or Identifier of the logical channel.

10. The remote UE of claim 8, wherein the first indication comprises at least one of: Radio Resource Control RRC messages; Information element IE in RRC message; Downlink control information DCI; Media Access Control Element MAC CE; Control protocol data unit PDU of the side link relay adaptation protocol SRAP layer; or Control PDU of the RLC layer.

11. The remote UE of claim 8, wherein the first indication is associated with at least one of a DRB configured for the direct path or a DRB configured for the indirect path.

12. The remote UE of claim 8, wherein in a case where the first indication is received from the BS, the processor is further configured to: A second indication indicating activation or deactivation of simultaneous transmission on multiple paths of the DRB is transmitted to the relay UE.

13. The remote UE of claim 11, wherein the processor is further configured to: receiving a response to the second indication from the relay UE, wherein the response comprises at least one of: a confirmation of the activation or deactivation; a message; an acknowledgement ACK; or a hybrid automatic repeat request acknowledgement HARQ ACK; or The response comprises at least one of: a rejection of the activation or deactivation; a message; a negative acknowledgement (NACK); or a hybrid automatic repeat request negative acknowledgement (HARQ) (NACK).

14. A base station BS, comprising: Transceiver; and a processor coupled to the transceiver and configured to: transmitting configuration information associated with a data radio bearer (DRB) of a remote UE; and A first indication is transmitted to at least one of the remote UE or a relay UE indicating activation or deactivation of simultaneous transmission on multiple paths of the DRB for the remote UE, wherein the multiple paths include at least one direct path and an indirect path.

15. The BS of claim 14, wherein the processor is further configured to: The same transmission or different transmissions are performed on the multiple paths to the remote UE.

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