Information receiving method and apparatus, information transmitting method and apparatus, and communication system

Abstract

The present application provides an information receiving apparatus and method, an information transmitting apparatus and method, and a communication system. The information transceiving method comprises: a first remote UE communicates with at least one second remote UE via a relay UE; and the first remote UE receives a notification message sent by the relay UE, the notification message being used for indicating a radio link failure between the relay UE and the at least one second remote UE.

Description

Information receiving and sending method and device, and communication system Technical Field

[0001] The embodiments of the present application relate to the field of wireless communication technologies. Background Art

[0002] The 3rd Generation Partnership Project (3GPP) introduced new technologies during the standardization of the fifth generation mobile communication technology (5G). These technologies allow user equipment (UE) to directly discover and / or communicate with each other using sidelink (SL) communication technology. The sidelink interface is also called the PC5 interface. For example, vehicle-to-everything (V2X) communication, public safety (PS) communication, and direct file transfer between UEs can rely on communication over the sidelink interface.

[0003] In Release 18, UE-to-UE relay (U2U relay) is being studied, where UE-to-UE relay refers to the "source user equipment (Source UE)" and "destination user equipment (Destination UE)" (which can also be referred to as "source remote UE" and "destination remote UE" respectively, or the "source user equipment" and "destination user equipment" are collectively referred to as "remote user equipment (remote UE)") communicating via the "relay user equipment (Relay UE)", where sidelink communication is used between the Source UE and the Relay UE, and sidelink communication is used between the Relay UE and the Destination UE, thereby effectively expanding the coverage of the sidelink transmission between the Source UE and the Destination UE and saving the transmission power of the remote UE.

[0004] It should be noted that the above introduction to the technical background is merely intended to provide a clear and complete description of the technical solutions of this application and facilitate understanding by those skilled in the art. Simply because these solutions are described in the background technology section of this application, it should not be assumed that the above technical solutions are well known to those skilled in the art.

[0005] Summary of the Invention

[0006] In the research on U2U relay in Release 18, it was agreed to use the user plane protocol stack and control plane protocol stack that introduced the adaptation (ADAPT) layer. This adaptation layer can also be called the SRAP (Sidelink Relay Adaptation Protocol) layer.

[0007] In 3GPP, a remote UE (remote UE) can communicate with at least one opposite remote UE (opposite remote UE) through the same relay UE (relay UE). When the relay UE detects a PC5 radio link failure (Radio Link Failure, RLF) with the opposite remote UE, the relay UE sends a NotificationMessageSidelink message to the remote UE. The message includes a side link indication type (sl-IndicationType) information element, which is set to relayUE-PC5-RLF.

[0008] When the remote UE receives the NotificationMessageSidelink message, when the sl-IndicationType information element is set to relayUE-PC5-RLF, the remote UE instructs the upper layer (V2X layer or NAS layer) to trigger the reselection of the U2U relay UE. If the remote UE is the source remote UE (Source remote UE), the corresponding remote UE is the destination remote UE (Destination remote UE); conversely, if the remote UE is the destination remote UE (Destination remote UE), the corresponding remote UE is the source remote UE (Source remote UE).

[0009] However, the inventors discovered that, for example, when the relay UE detects that a PC5 radio link failure (PC5RLF or sidelink RLF or SL RLF, hereinafter referred to as "radio link failure") occurs between it and one of the remote UEs at the opposite end, the relay UE sends a NotificationMessageSidelink message to the remote UE. At this time, the side links between the relay UE and the other remote UEs at the opposite end may still be able to communicate normally, that is, the communication between the remote UE and the other remote UEs relayed by the relay UE is not affected. However, based on the existing NotificationMessageSidelink message, if the sl-IndicationType information element is set to relayUE-PC5-RLF, the remote UE does not know with which remote UE the communication cannot proceed normally, nor does it know what to do after receiving the NotificationMessageSidelink message.

[0010] Currently, there are no relevant regulations on what information the NotificationMessageSidelink message sent by the relay UE to the remote UE contains, and how the remote UE processes the NotificationMessageSidelink message after receiving it.

[0011] In order to solve at least one of the above problems or other similar problems, the embodiments of the present application provide an information receiving method and device, an information sending method and device, and a communication system.

[0012] According to one aspect of an embodiment of the present application, a method for receiving information is provided, applied to a first remote UE, the method including:

[0013] communicating with at least one second remote UE via the relay UE;

[0014] Receive a notification message sent by the relay UE; the notification message is used to indicate that a radio link between the relay UE and at least one of the second remote UEs has failed.

[0015] According to another aspect of an embodiment of the present application, there is provided an information receiving apparatus, configured at a first remote UE, the apparatus comprising:

[0016] a first communication unit, configured to communicate with at least one second remote UE via the relay UE;

[0017] The first receiving unit is configured to receive a notification message sent by the relay UE, where the notification message is used to indicate that a radio link between the relay UE and at least one of the second remote UEs has failed.

[0018] An embodiment of the present application further provides an information sending method, applied to a relay UE, the method comprising:

[0019] communicating with a first remote UE and at least one second remote UE;

[0020] A notification message is sent to the first remote UE, where the notification message is used to indicate that a radio link between the relay UE and at least one second remote UE has failed.

[0021] The embodiment of the present application further provides an information sending device, which is applied to a relay UE. The device includes:

[0022] A second communication unit, configured to communicate with the first remote UE and at least one second remote UE;

[0023] A first sending unit is configured to send a notification message to the first remote UE, where the notification message is used to indicate that a radio link between the relay UE and at least one of the second remote UEs has failed.

[0024] According to another aspect of an embodiment of the present application, a communication system is provided, the system comprising:

[0025] A first remote UE, the first remote UE being configured to execute the above-mentioned information receiving method on the first remote UE side;

[0026] A relay UE, the relay UE being configured to execute the above-mentioned information sending method on the relay UE side; and

[0027] At least one second remote UE is configured to communicate with the first remote UE via the relay UE.

[0028] The beneficial effect of the embodiments of the present application is that: in UE-to-UE relay, a remote UE communicates with at least one opposite remote UE through the same relay UE, and the relay UE detects the radio link failure (RLF) of the opposite remote UE and sends a notification message to the remote UE to indicate the radio link failure of at least one opposite remote UE. As a result, the remote UE can perform relevant operations when the radio link fails on some (including one or more than one) or all (i.e., all) opposite remote UEs according to the notification message.

[0029] With reference to the following description and drawings, specific embodiments of the present application are disclosed in detail, indicating the manner in which the principles of the present application can be employed. It should be understood that the embodiments of the present application are not limited in scope thereby. Within the scope of the terms of the appended claims, the embodiments of the present application include many variations, modifications, and equivalents.

[0030] Features described and / or illustrated with respect to one embodiment may be used in the same or similar manner in one or more other embodiments, combined with features in other embodiments, or substituted for features in other embodiments.

[0031] It should be emphasized that the term "include / comprising" when used herein refers to the presence of features, integers, steps or components, but does not exclude the presence or addition of one or more other features, integers, steps or components. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The elements and features described in one figure or one embodiment of the present application can be combined with the elements and features shown in one or more other figures or embodiments. In addition, in the accompanying drawings, similar reference numerals represent corresponding parts in several figures and can be used to indicate corresponding parts used in more than one embodiment.

[0033] The included drawings are used to provide a further understanding of the embodiments of the present application, which constitute a part of the specification, are used to illustrate the implementation methods of the present application, and together with the text description, explain the principles of the present application. Obviously, the drawings described below are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without inventive work. In the drawings:

[0034] FIG1 is a schematic diagram of a system protocol stack architecture according to an embodiment of the present application;

[0035] FIG2 is a schematic diagram of a scenario according to an embodiment of the present application;

[0036] FIG3 is another schematic diagram of a scenario according to an embodiment of the present application;

[0037] FIG4 is a schematic diagram of an information receiving method according to an embodiment of the present application;

[0038] FIG5 is a schematic diagram of a method for sending information according to an embodiment of the present application;

[0039] FIG6 is another schematic diagram of the information sending method according to an embodiment of the present application;

[0040] FIG7 is a schematic diagram of a method for sending and receiving information according to an embodiment of the present application;

[0041] FIG8 is a schematic diagram of an information receiving device according to an embodiment of the present application;

[0042] FIG9 is a schematic diagram of an information sending device according to an embodiment of the present application;

[0043] FIG10 is a schematic diagram of the structure of a terminal device according to an embodiment of the present application. DETAILED DESCRIPTION

[0044] The foregoing and other features of the present application will become apparent from the following description with reference to the accompanying drawings. In the description and drawings, specific embodiments of the present application are disclosed, which illustrate some embodiments in which the principles of the present application can be employed. It should be understood that the present application is not limited to the described embodiments. On the contrary, the present application includes all modifications, variations, and equivalents falling within the scope of the appended claims. Various embodiments of the present application are described below with reference to the accompanying drawings. These embodiments are merely illustrative and are not intended to limit the present application.

[0045] In the embodiments of the present application, the terms "first", "second", etc. are used to distinguish different elements from the name, but do not indicate the spatial arrangement or temporal order of these elements, and these elements should not be limited by these terms. The term "and / or" includes any one and all combinations of one or more of the associated listed terms. The terms "comprising", "including", "having", etc. refer to the presence of the stated features, elements, components or components, but do not exclude the presence or addition of one or more other features, elements, components or components.

[0046] In the embodiments of this application, the singular forms "a," "the," etc. include plural forms and should be broadly understood to mean "a" or "a type" rather than being limited to "one." Furthermore, the term "said" should be understood to include both singular and plural forms, unless the context clearly indicates otherwise. Furthermore, the term "according to" should be understood to mean "at least in part based on...", and the term "based on" should be understood to mean "at least in part based on...", unless the context clearly indicates otherwise.

[0047] In the embodiments of the present application, the term "communication network" or "wireless communication network" may refer to a network that complies with any of the following communication standards, such as Long Term Evolution (LTE), enhanced Long Term Evolution (LTE-A, LTE-Advanced), Wideband Code Division Multiple Access (WCDMA), High-Speed ​​Packet Access (HSPA), etc.

[0048] Furthermore, communication between devices in the communication system may be carried out according to communication protocols of any stage, for example, including but not limited to the following communication protocols: 1G (generation), 2G, 2.5G, 2.75G, 3G, 4G, 4.5G, 5G, New Radio (NR) and future 6G, etc., and / or other currently known or future developed communication protocols.

[0049] In the embodiments of the present application, the term "network device" refers to, for example, a device in a communication system that connects a terminal device to the communication network and provides services to the terminal device. Network devices may include, but are not limited to, the following devices: base station (BS), access point (AP), transmission reception point (TRP), broadcast transmitter, mobile management entity (MME), gateway, server, radio network controller (RNC), base station controller (BSC), etc.

[0050] Base stations may include, but are not limited to, NodeB (NB), evolved NodeB (eNodeB or eNB), and 5G base stations (gNB), among others. They may also include remote radio heads (RRHs), remote radio units (RRUs), relays, or low-power nodes (e.g., femto, pico, etc.). The term "base station" may include some or all of their functions, and each base station may provide communication coverage for a specific geographic area. The term "cell" may refer to a base station and / or its coverage area, depending on the context in which the term is used.

[0051] In the embodiments of the present application, the term "user equipment" (UE) or "terminal equipment" (TE) refers to, for example, a device that accesses a communication network through a network device and receives network services. A user equipment may be fixed or mobile and may also be referred to as a mobile station (MS), a terminal, a subscriber station (SS), an access terminal (AT), a station, and so on.

[0052] Among them, user devices may include but are not limited to the following devices: cellular phones, personal digital assistants (PDAs), wireless modems, wireless communication devices, handheld devices, machine-type communication devices, laptop computers, cordless phones, smartphones, smart watches, digital cameras, wearable devices, etc.

[0053] For another example, in scenarios such as the Internet of Things (IoT), the user equipment may also be a machine or device for monitoring or measurement, such as but not limited to: machine type communication (MTC) terminals, vehicle-mounted communication terminals, device-to-device (D2D) terminals, machine-to-machine (M2M) terminals, terminals that support sidelink communication, and the like.

[0054] In addition, the term "network side" or "network device side" refers to one side of the network, which can be a base station or one or more network devices as described above. The term "user side" or "terminal side" or "terminal device side" refers to the user or terminal side, which can be a UE or one or more terminal devices as described above. Unless otherwise specified herein, "device" can refer to either network equipment or terminal equipment.

[0055] Figure 1 is a schematic diagram of the system protocol stack architecture of an embodiment of the present application, including a user plane protocol stack diagram (as shown in the left figure of Figure 1) and a control plane protocol stack diagram (as shown in the right figure of Figure 1); as shown in Figure 1, on the link of the PC5 interface, the ADAPT layer is supported. In the user plane protocol stack diagram, the IP layer, SDAP (Service Data Adaptation Protocol) layer and PDCP (Packet Data Convergence Protocol) layer are located above the ADAPT layer, and the RLC (Radio Link Control) layer, MAC (Media Access Control) layer and PHY (Physical) layer are located below the ADAPT layer; in the control plane protocol stack diagram, the RRC (Radio Resource Control) layer and PDCP layer are located above the ADAPT layer, and the RLC layer, MAC layer and PHY layer are located below the ADAPT layer. Optionally, the ADAPT in Figure 1 can be replaced with SRAP, and this application does not limit this. In the user plane protocol stack diagram, the IP layer, SDAP layer, and PDCP layer are terminated between two remote UEs, while the RLC layer, MAC layer, and PHY layer are terminated in each PC5 link; in the control plane protocol stack diagram, the RRC layer and PDCP layer are terminated between two remote UEs, while the RLC layer, MAC layer, and PHY layer are terminated in each PC5 link.

[0056] The following describes the scenarios of the embodiments of the present application through examples, but the present application is not limited thereto.

[0057] FIG2 is a schematic diagram of a scenario of an embodiment of the present application. For simplicity, FIG2 only schematically illustrates the signaling interaction and data transmission method between a UE-to-UE relay user equipment (UE-to-UE relay UE, U2U relay UE), i.e., a relay UE 203, and a first remote UE (first remote UE) 201 and a second remote UE 202. Wherein, the number of the second remote UE 202 is at least one, and FIG2 takes two second remote UEs 202-1 and 202-2 as an example, but the present application is not limited thereto. Furthermore, the first remote UE 201 can also be expressed as a transmitting remote UE (Transmission remote UE), a source remote UE (Source remote UE), a receiving remote UE (Receiving remote UE), a destination remote UE (Destination remote UE) or a target remote UE (Target remote UE), etc., and the second remote UE (second remote UE) 202 can also be expressed as a receiving remote UE (Receiving remote UE), a destination remote UE (Destination remote UE), a target remote UE (Target remote UE), a transmitting remote UE (Transmission remote UE) or a source remote UE (Source remote UE) corresponding to the first remote UE. As shown in FIG2 , the first remote UE 201 and the relay UE 203, as well as the second remote UE 202 and the relay UE 203, adopt a PC5 interface and use sidelink communication; the first remote UE 201 to the relay UE is the first hop (1 st hop), the relay UE to the second remote UE is the second hop (2 nd hop). Among them, UE-to-UE relay is being studied in Release 18. UE-to-UE relay can extend the coverage of side link transmission between two remote UEs and save power. The scenarios of this application include at least one of the following scenarios:

[0058] All UEs (first remote UE, relay UE, second remote UE) are within network coverage;

[0059] All UEs (first remote UE, relay UE, second remote UE) are out of network coverage; or,

[0060] Partial coverage, wherein at least one UE (first remote UE, Relay UE or second remote UE) is within the network coverage, and at least one UE (first remote UE, Relay UE or second remote UE) is outside the network coverage.

[0061] The protocol stack structures of the relay UE 203, the first remote UE 201 and the second remote UE 202 in FIG. 2 may refer to the protocol stack in FIG. 1 , and are not described repeatedly here.

[0062] FIG3 is another schematic diagram of a scenario of an embodiment of the present application. As shown in FIG3 , in U2U relay, a first remote UE 201 communicates with at least one (two are used as an example in FIG3 ) second remote UE 202 (also referred to as the remote UE of the first remote UE) through the same relay UE 203 (relay UE), and the relay UE 203 detects that the PC5 wireless link with at least one second remote UE 202 fails. For example, the relay UE in FIG3 detects that the PC5 wireless link with the second remote UE 202-2 fails. The inventors found that regardless of whether the side link between the relay UE and the second remote UE 202-1 can communicate normally, the relay UE 203 will send a NotificationMessageSidelink message to the first remote UE 201. However, based on the existing NotificationMessageSidelink message (sl-IndicationType information element is set to relayUE-PC5-RLF), the first remote UE 201 does not know which second remote UE 202 is unable to communicate normally with, nor does it know what to do after receiving the NotificationMessageSidelink message. Therefore, what information does the NotificationMessageSidelink message sent by the relay UE 203 to the first remote UE 201 contain, and how the remote UE processes the NotificationMessageSidelink message after receiving it are issues that need to be addressed.

[0063] In response to at least one of the above problems, embodiments of the present application provide an information receiving method and device, an information sending method and device, and a communication system.

[0064] Embodiments of the first aspect

[0065] FIG4 is a schematic diagram of an information receiving method according to an embodiment of the present application. As shown in FIG3 and FIG4, the method is applied to a first remote UE, and the method includes:

[0066] 401, communicating with at least one second remote UE via a relay UE;

[0067] 402 : Receive a notification message sent by the relay UE, where the notification message is used to indicate that a radio link between the relay UE and at least one of the second remote UEs has failed.

[0068] According to the above embodiment, in the UE-to-UE relay, the first remote UE communicates with at least one second remote UE through the same relay UE, and the relay UE detects a radio link failure (RLF) to the at least one second remote UE and sends a notification message to the first remote UE, where the notification message indicates that the radio link between the relay UE and at least one opposite remote UE has failed. As a result, the remote UE can learn from the notification message which (one) or which (more than one) or all opposite remote UEs cannot communicate normally, so as to perform relevant operations on the opposite remote UE when the radio link fails, thereby solving the above-mentioned problems existing in the prior art.

[0069] It is worth noting that FIG4 is merely a schematic illustration of an embodiment of the present application, and the present application is not limited thereto. For example, the execution order of the various operations may be appropriately adjusted, and other operations may be added or some operations may be removed. Those skilled in the art may make appropriate modifications based on the above description, and are not limited to the description of FIG4 .

[0070] In some embodiments, the first remote UE may be a source remote UE, and the second remote UE may be a destination remote UE, and vice versa, which will not be described in detail here.

[0071] In some embodiments, in 401, the first remote UE communicates with at least one second remote UE through a relay UE. The number of the second remote UEs can be one or more than one. For example, in the scenario shown in Figure 3, the number of second remote UEs is two, and this application does not impose any restrictions on this.

[0072] In some embodiments, in 401, the relay UE and the second remote UE communicate via a wireless link, which is a PC5 wireless link or a PC5 unicast link or a side link (sidelink), and the corresponding wireless link failure is called a PC5 radio link failure (PC5RLF) or a sidelink radio link failure (Sidelink RLF).

[0073] In some embodiments, in step 402, the first remote UE receives a notification message sent by the relay UE. The notification message may indicate that a radio link failure has occurred between the relay UE and some of the second remote UEs (e.g., one or more second remote UEs), or between the relay UE and all (or all) of the second remote UEs. Thus, the remote UE can learn from the notification message which one, some, or all of the remote UEs on the other end are unable to communicate normally.

[0074] In some embodiments, in 402, the notification message sent by the relay UE and received by the first remote UE includes identification information related to the radio link failure. The notification message can be sent via a PC5-RRC message, and the notification message can be an existing NotificationMessageSidelink message or a new PC5-RRC message different from the existing PC5-RRC message. The identification information related to the radio link failure in the notification message includes identification information related to at least one second remote UE with a radio link failure. For example, the identification information related to the second remote UE is identification information that can be mapped to the second remote UE, or identification information that can be mapped to the PC5 connection or side link between the relay UE and the second remote UE, or identification information that can be mapped to the PC5 connection or side link between the first remote UE and the second remote UE. The first remote UE can determine the second remote UE associated with / corresponding to the identification information based on the identification information. For example, the first remote UE determines the second remote UE associated with / corresponding to the identification information based on the identification information and the association / correspondence between the identification information and the second remote UE or the application or service of the second remote UE. The association / correspondence information may be information stored when the first remote UE leaves the factory, or may be information configured on the network side or configured by the relay UE and stored in the first remote UE, or may be determined by the first remote UE based on service mapping-related rules. Furthermore, the identification information may include one or more than one. When the identification information is one, the notification message indicates that the relay UE has detected a radio link failure with one second remote UE. When the identification information is more than one, the notification message indicates that the relay UE has detected a radio link failure with more than one second remote UE. Thus, the first remote UE can determine at least one second remote UE for which the relay UE has detected a radio link failure based on the identification information related to the radio link failure in the notification message. The method for the relay UE to detect a radio link failure with a second remote UE may refer to the prior art and will not be described in detail here.

[0075] In some embodiments, the identification information includes: a Layer 2 (L2) identifier (L2ID) of the second remote UE; or a pair of L2 identifiers of a first remote UE and a second remote UE. For example, the L2 identifier of the first remote UE may be determined by the V2X layer of the first remote UE according to an existing method, and the L2 identifier of the second remote UE may be determined by the V2X layer of the second remote UE according to an existing method and notified to the first remote UE. The length of the L2 identifier is 24 bits.

[0076] In some embodiments, the identification information includes: a local ID of the second remote UE, where the local ID of the second remote UE is notified to the first remote UE by the relay UE. For example, the local ID of the second remote UE is assigned to the second remote UE by the relay UE, and during data transmission between the first remote UE and the second remote UE, the local ID of the second remote UE is included in an SRAP header.

[0077] In some embodiments, the identification information includes: a pair of a local identification of a first remote UE and a local identification of a second remote UE, i.e., a pair of local identifications of the first remote UE and the second remote UE. For example, the local identification of the first remote UE is assigned to the first remote UE by a relay UE, and the local identification of the second remote UE is assigned to the second remote UE by the relay UE, and notified to the first remote UE by the relay UE. During data transmission between the first remote UE and the second remote UE, the pair of local identifications of the first remote UE and the second remote UE are included in an SRAP header.

[0078] The length of the local identifier of the first remote UE and the local identifier of the second remote UE may be less than 24 bits, for example, 4 bits, 8 bits, or 12 bits. Assuming that the length of the local ID of the first remote UE and the local ID of the second remote UE are both 8 bits, the length of the local identifier of the first remote UE and the local identifier of the second remote UE is 16 bits. For the specific content and determination method of the local identifier, please refer to the prior art and this application does not limit this.

[0079] In some embodiments, when the notification message includes identification information related to the radio link failure, as described above, the first remote UE can determine at least one second remote UE that has experienced a radio link failure with the relay UE based on the identification information. Therefore, the method further includes (not shown in the figure): the first remote UE performs relevant operations on the at least one second remote UE that has experienced a radio link failure with the relay UE. For example, the first remote UE performs relevant operations on the second remote UE corresponding to / associated with the identification information. Thus, in UE-to-UE relay, when a first remote UE communicates with more than one (or at least two) second remote UEs via the same relay UE, if the relay UE detects that the radio link has failed for some (one or more than one, but not all) of the second remote UEs, that is, the radio link between at least one second remote UE and the relay UE is still communicating normally, the first remote UE performs relevant operations on the part (one or more than one) of the second remote UEs that have experienced a radio link failure based on the notification message reported by the relay UE, and the communication with the second remote UEs whose radio links are normal with the relay UE is not affected. In this way, service interruption between the first remote UE and the second remote UE that can communicate normally can be avoided, thereby improving user experience.

[0080] In some embodiments, the related operations performed by the first remote UE on the at least one second remote UE determined according to the notification message include at least one of the following operations:

[0081] (1) Indicating information of the at least one second remote UE to an upper layer, the information including at least one of the following information: an L2 identifier of the second remote UE, a PC5 unicast link identifier between the first remote UE and the second remote UE, and a pair of the L2 identifier of the first remote UE and the L2 identifier of the second remote UE.

[0082] (2) Instructing an upper layer to trigger reselection of a relay UE for the at least one second remote UE.

[0083] (3) Determine / consider that a radio link failure is detected for the at least one second remote UE.

[0084] (4) Release the PC5-RRC connection with the at least one second remote UE.

[0085] (5) Instructing the upper layer to release the PC5-RRC connection with the at least one second remote UE.

[0086] (6) When the first remote UE is in an RRC connected state (RRC connected), perform a sidelink UE information process.

[0087] (7) Release all signaling radio bearers (SRBs) and / or data radio bearers (DRBs) between the second remote UE and the remote UE.

[0088] (8) Indicate to the upper layer that the PC5RLF for the second remote UE is received from the relay UE.

[0089] (9) Maintaining a connection with a second remote UE that communicates with the first remote UE via the relay UE and whose radio link with the relay UE has not failed. In some embodiments, the upper layer may include a V2X (Vehicle to Everything) layer or a NAS (Non-access stratum) layer, but is not limited thereto and is not enumerated herein.

[0090] The above operations (1) to (9) are described below.

[0091] For example, for operation (1), upon receiving the notification message from the relay UE, the first remote UE may indicate to the upper layer information about at least one second remote UE that has experienced a radio link failure. The information about the second remote UE is as described above and will not be repeated here.

[0092] In the case where the identification information related to the wireless link failure included in the notification message sent by the relay UE is the L2 identification of the second remote UE, if the first remote UE indicates the L2 identification of the second remote UE to the upper layer, the first remote UE can indicate the L2 identification of the second remote UE in the notification message to the upper layer.

[0093] In the case where the identification information related to the radio link failure included in the notification message sent by the relay UE is the local identification of the second remote UE, if the first remote UE indicates the L2 identification of the second remote UE to the upper layer, the first remote UE may convert the local identification of the second remote UE in the notification message into the L2 identification of the second remote UE, and then indicate the converted L2 identification of the second remote UE to the upper layer. The first remote UE determines the L2 identification of the second remote UE based on the local identification of the second remote UE and the association / correspondence between the local identification and the L2 identification or user information (including L2ID). The information of the association / correspondence may be information stored when the first remote UE leaves the factory, information configured on the network side or information configured by the relay UE and existing in the first remote UE, or information determined by the first remote UE based on rules related to service mapping.

[0094] In a case where the identification information related to the wireless link failure included in the notification message sent by the relay UE is a pair of L2 identifiers of a first remote UE and an L2 identifier of a second remote UE, if the first remote UE indicates a pair of L2 identifiers of the first remote UE and the L2 identifier of the second remote UE to the upper layer, the first remote UE can indicate the pair of L2 identifiers of the first remote UE and the L2 identifier of the second remote UE in the notification message to the upper layer.

[0095] In a case where the identification information related to the radio link failure included in the notification message sent by the relay UE is a pair of local identifiers of a first remote UE and a local identifier of a second remote UE, if the first remote UE indicates the pair of L2 identifiers of the first remote UE and the second remote UE to an upper layer, the first remote UE may convert the pair of local identifiers of the first remote UE and the second remote UE in the notification message into a pair of L2 identifiers of the first remote UE and the second remote UE, and then indicate the converted pair of L2 identifiers of the first remote UE and the second remote UE to the upper layer. For example, the first remote UE determines the L2 identifier of the first remote UE and the L2 identifier of the second remote UE based on the local identifier of the first remote UE, the local identifier of the second remote UE, and the association / correspondence between the local identifiers and the L2 identifiers, thereby obtaining the pair of L2 identifiers of the first remote UE and the second remote UE. The information of the association / correspondence relationship can be the information stored when the first remote UE leaves the factory, or it can be the information configured on the network side or the information configured by the relay UE and exists in the first remote UE, or it can be determined by the first remote UE according to rules related to service mapping.

[0096] For example, with respect to operation (2), upon / after receiving a notification message from the relay UE, the first remote UE instructs an upper layer to trigger reselection of the relay UE for the at least one second remote UE, for example, by indicating information about the at least one second remote UE. The process of the upper layer triggering reselection of the relay UE is described in the prior art and is not further described here. The information about the second remote UE is as described above and is not further described here.

[0097] For example, for operation (3), when / after receiving the notification message sent by the relay UE, the first remote UE determines / believes that a radio link failure has been detected for the at least one second remote UE based on the received notification message, for example, it is believed that a radio link failure has been detected for the PC5-RRC connection or PC5 unicast link (or side link) between the first remote UE and the at least one second remote UE.

[0098] For example, for operation (4), when / after the first remote UE receives the notification message sent by the relay UE, the RRC entity of the first remote UE releases the PC5-RRC connection between the first remote UE and the at least one second remote UE.

[0099] For example, for operation (5), upon / after receiving the notification message sent by the relay UE, the first remote UE instructs the upper layer to release the PC5-RRC connection between the first remote UE and the at least one second remote UE. "Instructing the upper layer to release the PC5-RRC connection between the first remote UE and the at least one second remote UE" means: reporting to the upper layer that "the first remote UE (such as the RRC layer of the first remote UE) has released the PC5-RRC connection between the first remote UE and the at least one second remote UE" or "the PC5-RRC connection or PC5 unicast link between the first remote UE and the at least one second remote UE is unavailable."

[0100] For example, for operation (6), when / after receiving the notification message sent by the relay UE, the first remote UE performs a sidelink UE information process when the first remote UE is in an RRC connected state. For example, the first remote UE sends a sidelink UE information message to a network device (e.g., a gNB), where the message includes fourth indication information, where the fourth indication information is used to indicate a radio link failure for at least one second remote UE. The sidelink UE information process can be implemented with reference to the prior art. The effect of the first remote UE performing operation (6) is, for example, that the first remote UE reports to the gNB that an end-to-end sidelink radio link failure (sidelink RLF, SL RLF) has occurred between the first remote UE and the second remote UE, or instructs the gNB to stop allocating sidelink (SL) resources to the second remote UE.

[0101] For example, in operation (7), when / after the first remote UE receives the notification message sent by the relay UE, the first remote UE releases all signaling radio bearers (SRBs) and / or data radio bearers (DRBs) between the first remote UE and the at least one second remote UE. As a result, the connection and service between the first remote UE and the second remote UE are interrupted.

[0102] For example, for operation (8), after receiving the notification message sent by the relay UE, the first remote UE indicates to the upper layer that the PC5RLF for the at least one second remote UE has been received from the relay UE, wherein “indicating to the upper layer that the PC5RLF for the at least one second remote UE has been received from the relay UE” means: “reporting to the upper layer that the PC5RLF for the at least one second remote UE has been received from the relay UE”. Optionally, after receiving the indication, the upper layer of the first remote UE may determine whether to trigger relay reselection.

[0103] For example, for operation (9), after the first remote UE receives the notification message sent by the relay UE, the first remote UE maintains connection with other second remote UEs other than at least one second remote UE determined according to the notification message, and the other second remote UE communicates with the first remote UE via the same relay UE. The first remote UE does not perform any operation on the other second remote UE whose wireless link has not failed as detected by the relay UE.

[0104] In some embodiments, the first remote UE may perform the above operations (1) to (9) individually, or may perform at least two of the above operations (1) to (9). In the case of performing at least two operations, the order of each operation may be determined according to the actual situation, for example, the at least two operations may be performed in sequence or simultaneously, or some of the at least two operations may be performed simultaneously, and the other operations may be performed in sequence, etc. For example, when performing operations (1), (2), and (9), they may be performed simultaneously or in sequence, which is not limited here; when performing operations (4) and (5), operation (4) may be performed first, and then operation (5); for example, when performing operations (3) and (5), operation (3) may be performed first, and then operation (5). Unless otherwise specified, this application does not limit the execution order of the associated execution of each operation.

[0105] In some embodiments, when the notification message includes identification information related to the failure of the wireless link, as described above, the first remote UE can determine at least one second remote UE with a failed wireless link based on the identification information. At this time, the method also includes: the first remote UE performs relevant operations on all second remote UEs that communicate with the first remote UE via the relay UE. For example, in UE-to-UE relay, when a first remote UE communicates with one or more (or at least two) second remote UEs via the same relay UE, if the relay UE detects that the wireless link to some of the second remote UEs has failed, that is, the wireless link between at least one second remote UE and the relay UE is still communicating normally, the first remote UE performs relevant operations on all (all) second remote UEs relayed via the relay UE based on the notification message reported by the relay UE. In this way, the complexity of the behavior of the first remote UE can be reduced, making the behavior of the first remote UE simple.

[0106] In some embodiments, in step 402, the notification message sent by the relay UE and received by the first remote UE does not include identification information related to the radio link failure. In this case, the method further includes (not shown): the first remote UE determines / considers (considers) that the radio link between the relay UE and all (all) second remote UEs has failed based on the notification message, and the first remote UE also considers that a radio link failure has been detected for all (all) second remote UEs. This reduces signaling overhead because the notification message does not need to include identification information.

[0107] In some embodiments, the method further includes (not shown): the first remote UE performs relevant operations on all second remote UEs communicating with the first remote UE via the relay UE. Thus, when the first remote UE believes that the radio link to all (all) second remote UEs has failed, the first remote UE performs relevant operations on all second remote UEs, simplifying the behavior of the first remote UE.

[0108] In some embodiments, when the first remote UE performs related operations on all second remote UEs that communicate with the first remote UE via the relay UE, the related operations performed by the first remote UE on all second remote UEs include:

[0109] (10) indicating information of all second remote UEs to an upper layer, the information including at least one of the following information: an L2 identifier of the second remote UE, a PC5 unicast link identifier between the first remote UE and the second remote UE, and a pair of L2 identifiers of the first remote UE and the second remote UE;

[0110] (11) instructing an upper layer to trigger reselection of relay UEs for all second remote UEs;

[0111] (12) determining / considering that the relay UE has detected a radio link failure for all the second remote UEs and / or determining / considering that a radio link failure has been detected for all the second remote UEs;

[0112] (13) releasing the PC5-RRC connections with all the second remote UEs;

[0113] (14) instructing the upper layer to release the PC5-RRC connection with all the second remote UEs;

[0114] (15) when the first remote UE is in an RRC connected state, executing a sidelink UE information process;

[0115] (16) releasing all SRBs and / or DRBs between the second remote UEs;

[0116] (17) Indicate to the upper layer that the PC5RLF for all second remote UEs has been received from the relay UE.

[0117] The above operations (10) to (17) correspond to the above operations (1) to (8) respectively. The only difference is that in operations (10) to (17), the first remote UE performs the operation on all second remote UEs relayed by the same relay UE, while in operations (1) to (8), the first remote UE performs the operation on at least one second remote UE whose radio link has failed as indicated in the notification message sent by the relay terminal. Therefore, operations (10) to (17) can be implemented with reference to the corresponding operations in the above text and will not be repeated here.

[0118] It can be seen from the above embodiments that in UE-to-UE relay, a first remote UE can communicate with at least one second remote UE (also referred to as the opposite remote UE) through the same relay UE. When the relay UE detects that the radio link to at least one second remote UE fails, it sends a notification message to the first remote UE, whereby the first remote UE can perform relevant operations when the radio link fails on some (one or more than one) or all (all) second remote UEs according to the notification message. The notification message may include identification information related to the radio link failure, and the identification information related to the radio link failure includes identification information related to at least one second remote UE with a failed radio link. Thus, the first remote UE can determine at least one second remote UE with a failed radio link based on the notification message, and then perform operations on the at least one second remote UE (part, not including all) or all (all) second remote UEs. When the first remote UE performs an operation on the at least one second remote UE, if the relay UE fails in its radio link to some of the second remote UEs, the communication of the second remote UEs whose radio links with the relay UE are normal will not be affected, thereby avoiding the service interruption time between the first remote UE and the second remote UEs that are still communicating normally, thereby improving the user experience. When the first remote UE performs relevant operations on all second remote UEs, the complexity of the behavior of the first remote UE can be reduced, making the behavior of the first remote UE simple. In addition, the notification message may not include identification information related to the radio link failure. After receiving the notification message, the first remote UE performs relevant operations on all second remote UEs, which can reduce signaling overhead and make the behavior of the first remote UE simple.

[0119] FIG5 is a schematic diagram of an information receiving method according to an embodiment of the present application. As shown in FIG3 and FIG5, the method is applied to a relay UE, and the method includes:

[0120] 501, communicating with a first remote UE and at least one second remote UE;

[0121] 502. Send a notification message to the first remote UE, where the notification message is used to indicate that a radio link between the relay UE and at least one of the second remote UEs has failed.

[0122] It is worth noting that FIG5 above is merely a schematic illustration of an embodiment of the present application, and the present application is not limited thereto. For example, the execution order of the various operations may be appropriately adjusted, and other operations may be added or some operations may be reduced. Those skilled in the art may make appropriate modifications based on the above description, and are not limited to the description of FIG5 above.

[0123] 501-502 of FIG. 5 correspond to 401-402 of FIG. 4 , respectively, and the same contents will not be repeated herein. In some embodiments, in 501, the first remote UE communicates with at least one second remote UE via the relay UE. The number of the second remote UEs may be one or more. For example, in the scenario shown in FIG. 3 , the number of the second remote UEs is two, and this application does not impose any limitation on this.

[0124] In some embodiments, in 501, communication is performed between the first remote UE and the relay UE, and between the relay UE and the second remote UE via a wireless link, which is a PC5 wireless link or a PC5 unicast link or a side link (sidelink). The corresponding wireless link failure is referred to as a PC5 radio link failure (PC5RLF) or a sidelink radio link failure (sidelink radio link failure, SL RLF).

[0125] In some embodiments, in 502, the notification message sent by the relay UE to the first remote UE includes identification information related to the radio link failure. The notification message is as described above, and its content is incorporated herein and will not be repeated here.

[0126] In some embodiments, the identification information includes: a Layer 2 (L2) identifier (L2ID) of the second remote UE; or a pair of L2 identifiers of a first remote UE and a second remote UE. For example, the L2 identifier of the first remote UE may be determined by the V2X layer of the first remote UE according to an existing method, and the L2 identifier of the second remote UE may be determined by the V2X layer of the second remote UE according to an existing method and notified to the first remote UE. The length of the L2 identifier is 24 bits.

[0127] In some embodiments, the identification information includes: a local ID of the second remote UE, where the local ID of the second remote UE is notified to the first remote UE by the relay UE. For example, the local ID of the second remote UE is assigned to the second remote UE by the relay UE, and during data transmission between the first remote UE and the second remote UE, the local ID of the second remote UE is included in an SRAP header.

[0128] In some embodiments, the identification information includes: a pair of a local identification of a first remote UE and a local identification of a second remote UE, i.e., a pair of local identifications of the first remote UE and the second remote UE. For example, the local identification of the first remote UE is assigned to the first remote UE by a relay UE, and the local identification of the second remote UE is assigned to the second remote UE by the relay UE, and notified to the first remote UE by the relay UE. During data transmission between the first remote UE and the second remote UE, the pair of local identifications of the first remote UE and the second remote UE are included in an SRAP header.

[0129] The length of the local identifier of the first remote UE and the local identifier of the second remote UE may be less than 24 bits, for example, 4 bits, 8 bits, or 12 bits. Assuming that the length of the local ID of the first remote UE and the local ID of the second remote UE are both 8 bits, the length of the local identifier of the first remote UE and the local identifier of the second remote UE is 16 bits. For the specific content and determination method of the local identifier, please refer to the prior art and this application does not limit this.

[0130] FIG6 is another schematic diagram of the information receiving method according to an embodiment of the present application. As shown in FIG3 and FIG6, the method is applied to a relay UE, and the method includes:

[0131] 601, communicating with a first remote UE and at least one second remote UE;

[0132] 602. Detect a radio link of a second remote UE that communicates with the first remote UE via the relay UE.

[0133] 603 : Send a notification message to the first remote UE, where the notification message is used to indicate that a radio link between the relay UE and at least one of the second remote UEs has failed.

[0134] It is worth noting that FIG6 above is merely a schematic illustration of an embodiment of the present application, and the present application is not limited thereto. For example, the execution order of the various operations may be appropriately adjusted, and other operations may be added or some operations may be reduced. Those skilled in the art may make appropriate modifications based on the above description, and are not limited to the description of FIG6 above.

[0135] Among them, 601 and 603 in Figure 6 are similar to 501 and 502 in Figure 5 respectively. The above content is merged here and the same content will not be repeated hereafter.

[0136] In some embodiments, in 602, the relay UE detects the wireless links between all second remote UEs communicating with the first remote UE via the relay UE. When it is detected that the wireless link between at least one second remote UE and the relay UE fails, the relay UE may execute the above step 603.

[0137] FIG7 is a schematic diagram of a method for sending and receiving information provided by an embodiment of the present application. The method is applied to the communication system shown in FIG2 or FIG3 , as shown in FIG7 , the method includes:

[0138] 701. The relay UE detects a radio link of a second remote UE that communicates with the first remote UE via the relay UE.

[0139] 702. When the relay UE detects that a radio link to at least one second remote UE fails, the relay UE sends a notification message to the first remote UE, where the notification message is used to indicate that the radio link between the relay UE and the at least one second remote UE fails.

[0140] Among them, the content of 701 in Figure 7 is similar to that of 602 in Figure 6, and the content of 702 in Figure 7 is similar to that of 502 in Figure 5. The above content is merged here and the same content will not be repeated hereafter.

[0141] In some embodiments, after 702, the method may further include:

[0142] 703. The first remote UE performs relevant operations on at least one second remote UE according to the notification message.

[0143] In some embodiments, when the notification message includes identification information related to the radio link failure, as described above, the first remote UE can determine at least one second remote UE that has experienced a radio link failure with the relay UE based on the identification information. Therefore, the first remote UE performs relevant operations on the at least one second remote UE that has experienced a radio link failure with the relay UE. For example, the first remote UE performs relevant operations on the second remote UE corresponding to / associated with the identification information. Thus, in UE-to-UE relay, when a first remote UE communicates with more than one (or at least two) second remote UEs via the same relay UE, if the relay UE detects that the radio link fails for some (one or more than one, but not all) second remote UEs, that is, the radio link between at least one second remote UE and the relay UE is still communicating normally, the first remote UE performs relevant operations only for the part (one or more than one) second remote UEs that have experienced a radio link failure based on the notification message reported by the relay UE, and the communication with the second remote UEs whose radio links are normal with the relay UE is not affected. In this way, service interruption between the first remote UE and the second remote UE that can communicate normally can be avoided, thereby improving user experience.

[0144] The first remote UE performs relevant operations on at least one second remote UE determined according to the notification message, such as at least one of the operations (1) to (9) described above. The contents of the above operations (1) to (9) are merged here and are not repeated here.

[0145] In some embodiments, when the notification message includes identification information related to the failure of the wireless link, as described above, the first remote UE can determine at least one second remote UE with a failed wireless link based on the identification information. At this time, the method also includes: the first remote UE performs relevant operations on all second remote UEs that communicate with the first remote UE via the relay UE. For example, in UE-to-UE relay, when a first remote UE communicates with one or more (or at least two) second remote UEs via the same relay UE, if the relay UE detects that the wireless link to some of the second remote UEs has failed, that is, the wireless link between at least one second remote UE and the relay UE is still communicating normally, the first remote UE performs relevant operations on all second remote UEs relayed via the relay UE based on the notification message reported by the relay UE. In this way, the complexity of the behavior of the first remote UE can be reduced, making the behavior of the first remote UE simple.

[0146] In some embodiments, in 702, the notification message sent by the relay UE and received by the first remote UE does not include identification information related to the failure of the wireless link. At this time, the method also includes (not shown): the first remote UE determines / considers (considers) that the wireless link between the relay UE and all (all) second remote UEs has failed based on the notification message, and the first remote UE may also consider that the wireless link failure has been detected for all (all) second remote UEs. Further, the method also includes 703-1: the first remote UE performs relevant operations on all second remote UEs that communicate with the first remote UE via the relay UE. Thus, in the case where the first remote UE considers that the wireless link for all (all) second remote UEs has failed, the first remote UE performs relevant operations on all second remote UEs, so that the behavior of the first remote UE is simple.

[0147] The first remote UE performs relevant operations on all second remote UEs that communicate with the first remote UE via the relay UE, such as at least one of the operations (10) to (17) mentioned above. The contents of the above operations (10) to (17) are merged here and are not repeated here.

[0148] It can be seen from the above embodiments that in UE-to-UE relay, a first remote UE can communicate with at least one second remote UE (also referred to as the opposite remote UE) through the same relay UE. When the relay UE detects that the radio link to at least one second remote UE fails, it sends a notification message to the first remote UE, whereby the first remote UE can perform relevant operations when the radio link fails on some (one or more than one, not including all) or all (all) second remote UEs according to the notification message. The notification message may include identification information related to the radio link failure, and the identification information related to the radio link failure includes identification information related to at least one second remote UE with a failed radio link. Thus, the first remote UE can determine at least one second remote UE with a failed radio link according to the notification message, and then perform operations on the at least one second remote UE (part, not including all) or all (all) second remote UEs. When the first remote UE performs an operation on the at least one second remote UE, if the relay UE fails in its radio link to some of the second remote UEs, the communication of the second remote UEs whose radio links with the relay UE are normal will not be affected, thereby avoiding the service interruption time between the first remote UE and the second remote UEs that are still communicating normally, thereby improving the user experience. When the first remote UE performs relevant operations on all second remote UEs, the complexity of the behavior of the first remote UE can be reduced, making the behavior of the first remote UE simple. In addition, the notification message may also not include identification information related to the radio link failure. After receiving the notification message, the first remote UE performs relevant operations on all second remote UEs, making the behavior of the first remote UE simple.

[0149] Embodiments of the second aspect

[0150] An embodiment of the present application provides an information receiving device, which is applied to a first remote UE. FIG8 is a schematic diagram of the information receiving device. The information receiving device and the information receiving method in the embodiment of the first aspect provided by the present application are based on the same inventive concept and have similar principles for solving problems. Therefore, the implementation of the information receiving device refers to the implementation of the information receiving method in the embodiment of the first aspect provided by the present application, and repeated parts will not be repeated. As used below, the term "unit" or "module" can be a combination of software and / or hardware that implements predetermined functions. Although the system described in the following embodiments is preferably implemented in software, implementation in hardware, or a combination of software and hardware, is also possible and conceivable.

[0151] As shown in FIG8 , the information receiving device includes:

[0152] A first communication unit 801 is configured to communicate with at least one second remote UE via a relay UE;

[0153] The first receiving unit 802 is configured to receive a notification message sent by the relay UE, where the notification message is used to indicate that a radio link between the relay UE and at least one of the second remote UEs has failed.

[0154] In some embodiments, the first communication unit 801 communicates with at least one second remote UE through a relay UE. The number of the second remote UEs may be one or more. For example, in the scenario shown in FIG3 , the number of the second remote UEs is two, and this application does not impose any restrictions on this. The first communication unit 801 and the relay UE, and the relay UE and the second remote UE communicate via a wireless link. The wireless link is a PC5 wireless link or a PC5 unicast link or a side link (sidelink). The corresponding radio link failure is referred to as a PC5 radio link failure (PC5RLF) or a sidelink radio link failure (Sidelink RLF).

[0155] In some embodiments, the first receiving unit 802 receives a notification message sent by the relay UE, where the notification message may indicate that a radio link between the relay UE and some of the second remote UEs (e.g., one or more of the second remote UEs) or all (all) of the second remote UEs has failed. Thus, the remote UE can learn, based on the notification message, which one or more or all of the remote UEs at the other end cannot communicate normally.

[0156] In some embodiments, the notification message includes identification information related to the radio link failure.

[0157] The notification message can be sent via a PC5-RRC message, which can be an existing NotificationMessageSidelink message or a new PC5-RRC message different from the existing PC5-RRC message. The identification information related to the radio link failure in the notification message includes identification information related to at least one second remote UE with a radio link failure. For example, the identification information related to the second remote UE is identification information that can be mapped to the second remote UE, or identification information that can be mapped to the PC5 connection or side link between the relay UE and the second remote UE, or identification information that can be mapped to the PC5 connection or side link between the first remote UE and the second remote UE. The first remote UE can determine the second remote UE associated with / corresponding to the identification information based on the identification information. For example, the first remote UE determines the second remote UE associated with / corresponding to the identification information based on the identification information and the association / correspondence between the identification information and the second remote UE or the application or service of the second remote UE. The information of the association / correspondence relationship may be the information stored when the first remote UE leaves the factory, or the information configured on the network side or the information configured by the relay UE and existing in the first remote UE, or may be determined by the first remote UE according to rules related to service mapping. In addition, the identification information may include 1 or more than 1. When the identification information is 1, the notification message indicates that the relay UE has detected a failure of the radio link with a second remote UE. When the identification information is more than 1, the notification message indicates that the relay UE has detected a failure of the radio link with more than 1 second remote UE. Thus, the first remote UE can determine at least one second remote UE with which the relay UE has detected a failure of the radio link based on the identification information related to the radio link failure in the notification message. The method for the relay UE to detect a failure of the radio link with the second remote UE can refer to the prior art and will not be described in detail here.

[0158] In some embodiments, the identification information includes: a Layer 2 (L2) identifier (L2ID) of the second remote UE; or a pair of L2 identifiers of a first remote UE and a second remote UE. For example, the L2 identifier of the first remote UE may be determined by the V2X layer of the first remote UE according to an existing method, and the L2 identifier of the second remote UE may be determined by the V2X layer of the second remote UE according to an existing method and notified to the first remote UE. The length of the L2 identifier is 24 bits.

[0159] In some embodiments, the identification information includes: a local ID of the second remote UE, where the local ID of the second remote UE is notified to the first remote UE by the relay UE. For example, the local ID of the second remote UE is assigned to the second remote UE by the relay UE, and during data transmission between the first remote UE and the second remote UE, the local ID of the second remote UE is included in an SRAP header.

[0160] In some embodiments, the identification information includes: a pair of a local identification of a first remote UE and a local identification of a second remote UE, i.e., a pair of local identifications of the first remote UE and the second remote UE. For example, the local identification of the first remote UE is assigned to the first remote UE by a relay UE, and the local identification of the second remote UE is assigned to the second remote UE by the relay UE, and notified to the first remote UE by the relay UE. During data transmission between the first remote UE and the second remote UE, the pair of local identifications of the first remote UE and the second remote UE are included in an SRAP header.

[0161] The length of the local identifier of the first remote UE and the local identifier of the second remote UE may be less than 24 bits, for example, 4 bits, 8 bits, or 12 bits. Assuming that the length of the local ID of the first remote UE and the local ID of the second remote UE are both 8 bits, the length of the local identifier of the first remote UE and the local identifier of the second remote UE is 16 bits. For the specific content and determination method of the local identifier, please refer to the prior art and this application does not limit this.

[0162] In some embodiments, when the notification message includes identification information related to the radio link failure, as described above, the first remote UE can determine at least one second remote UE that has experienced a radio link failure with the relay UE based on the identification information. Therefore, the information receiving device also includes a first operating unit 603 (not shown), which is used to: perform relevant operations on the at least one second remote UE. For example, the first remote UE performs relevant operations on the second remote UE corresponding to / associated with the identification information. Thus, in UE-to-UE relay, when a first remote UE communicates with more than one (or at least two) second remote UEs via the same relay UE, if the relay UE detects that the radio link fails for some (one or more than one, but not all) second remote UEs, that is, the radio link between at least one second remote UE and the relay UE is still communicating normally, the first remote UE performs relevant operations only on the part (one or more than one) second remote UEs that have experienced a radio link failure based on the notification message reported by the relay UE, and the communication with the second remote UEs whose radio links with the relay UE are normal is not affected. In this way, service interruption between the first remote UE and the second remote UE that can communicate normally can be avoided, thereby improving user experience.

[0163] In some embodiments, the related operation includes at least one of the following:

[0164] (1) indicating information of the at least one second remote UE to an upper layer, the information including at least one of the following information: an L2 identifier of the second remote UE, a PC5 unicast link identifier between the first remote UE and the second remote UE, and a pair of an L2 identifier of the first remote UE and an L2 identifier of the second remote UE;

[0165] (2) instructing an upper layer to trigger reselection of a relay UE for the at least one second remote UE;

[0166] (3) determining / considering that a radio link failure is detected for the at least one second remote UE;

[0167] (4) releasing the PC5-RRC connection with the at least one second remote UE;

[0168] (5) instructing an upper layer to release the PC5-RRC connection with the at least one second remote UE;

[0169] (6) when the first remote UE is in an RRC connected state, executing a sidelink UE information process;

[0170] (7) releasing all SRBs and / or DRBs between the second remote UE and the second remote UE;

[0171] (8) Indicate to the upper layer that the PC5RLF for the second remote UE has been received from the relay UE;

[0172] (9) Maintaining connection with a second remote UE that communicates with the first remote UE via the relay UE and whose radio link with the relay UE has not failed.

[0173] In some embodiments, the upper layer includes a V2X layer or a NAS layer.

[0174] The relevant operations (1) to (9) in the above embodiment and the types of operations (1) to (9) in the embodiment of the first aspect can be implemented with reference to each other and will not be repeated here.

[0175] In some embodiments, when the notification message includes identification information related to the failure of the wireless link, as described above, the first remote UE can determine at least one second remote UE with a failed wireless link based on the identification information. At this time, the first operation unit 803 (not shown) can also be used for: the first remote UE performs relevant operations on all second remote UEs that communicate with the first remote UE via the relay UE. For example, in UE-to-UE relay, when a first remote UE communicates with one or more (or at least two) second remote UEs via the same relay UE, if the relay UE detects that the wireless link to some of the second remote UEs has failed, that is, the wireless link between at least one second remote UE and the relay UE is still communicating normally, the first remote UE performs relevant operations on all second remote UEs relayed via the relay UE based on the notification message reported by the relay UE. In this way, the complexity of the behavior of the first remote UE can be reduced, and the behavior of the first remote UE can be simplified.

[0176] In some embodiments, the notification message sent by the relay UE and received by the first remote UE does not include identification information related to the radio link failure. At this time, the first remote UE determines / considers (considers) that the radio link between the relay UE and all (all) second remote UEs has failed based on the notification message, and the first remote UE also considers that the radio link failure has been detected for all (all) second remote UEs. The information receiving device also includes a second operation unit 604 (not shown): the first remote UE performs relevant operations on all second remote UEs that communicate with the first remote UE via the relay UE. Thus, in the case where the first remote UE believes that the radio link for all (all) second remote UEs has failed, the first remote UE performs relevant operations on all second remote UEs, so that the behavior of the first remote UE is simple.

[0177] In some embodiments, the operations performed by the first remote UE on all second remote UEs communicating with the first remote UE via the relay UE include at least one of the following:

[0178] (10) indicating information of all second remote UEs to an upper layer, the information including at least one of the following information: an L2 identifier of the second remote UE, a PC5 unicast link identifier between the first remote UE and the second remote UE, and a pair of L2 identifiers of the first remote UE and the second remote UE;

[0179] (11) instructing an upper layer to trigger reselection of relay UEs for all second remote UEs;

[0180] (12) determining that the relay UE has detected a radio link failure for all the second remote UEs and / or determining / considering that a radio link failure has been detected for all the second remote UEs;

[0181] (13) releasing the PC5-RRC connections with all the second remote UEs;

[0182] (14) instructing the upper layer to release the PC5-RRC connection with all the second remote UEs;

[0183] (15) when the first remote UE is in an RRC connected state, executing a sidelink UE information process;

[0184] (16) releasing all SRBs and / or DRBs between the second remote UEs;

[0185] (17) Indicate to the upper layer that the PC5RLF for all second remote UEs has been received from the relay UE.

[0186] The relevant operations (10) to (17) in the above embodiment are similar to the types of operations (10) to (17) in the embodiment of the first aspect, and can be implemented with reference to them, and will not be repeated here.

[0187] The embodiment of the present application also provides an information sending device, and Figure 7 is a schematic diagram of the information sending device. The information sending device and the information sending method in the embodiment of the first aspect provided by the present application are based on the same inventive concept and have similar principles for solving problems. Therefore, for the implementation of the information sending device, please refer to the implementation of the information sending method in the embodiment of the first aspect provided by the present application, and the repeated parts will not be repeated. As used below, the term "unit" or "module" can be a combination of software and / or hardware that implements a predetermined function. Although the system described in the following embodiments is preferably implemented in software, implementation in hardware, or a combination of software and hardware, is also possible and conceived.

[0188] As shown in FIG9 , the information receiving device includes:

[0189] A second communication unit 901, configured to communicate with a first remote UE and at least one second remote UE;

[0190] The first sending unit 902 is configured to send a notification message to the first remote UE, where the notification message is used to indicate that a radio link between the relay UE and at least one of the second remote UEs has failed.

[0191] In some embodiments, the notification message includes identification information related to the radio link failure.

[0192] In some embodiments, the identification information includes at least one of the following information:

[0193] an L2 identifier of the second remote UE;

[0194] a local identifier of the second remote UE;

[0195] a pair of an L2 identifier of a first remote UE and an L2 identifier of a second remote UE; and

[0196] A pair of a local identifier of a first remote UE and a local identifier of a second remote UE.

[0197] In some embodiments, the local identifier of the first remote UE and / or the local identifier of the second remote UE are allocated by the relay UE.

[0198] In some embodiments, during data transmission between the first remote UE and the second remote UE, the local identifier of the first remote UE and the local identifier of the second remote UE are included in an SRAP header.

[0199] In some embodiments, the apparatus further comprises:

[0200] a detection unit, configured to detect a radio link between a second remote UE communicating with the first remote UE via the relay UE;

[0201] Furthermore, when the first sending unit detects that the radio link between the first sending unit and the at least one second remote UE fails, the first sending unit sends the notification message to the first remote UE.

[0202] In some embodiments, the notification message is sent via a PC5-RRC message.

[0203] In addition, for the sake of simplicity, Figures 8 and 9 only illustrate the connection relationships or signal paths between various components or modules. However, those skilled in the art should be aware that various related technologies such as bus connections can be used. The above-mentioned components or modules can be implemented by hardware facilities such as processors, memories, transmitters, and receivers; this application is not limited to this.

[0204] It can be seen from the above embodiments that in UE-to-UE relay, a first remote UE can communicate with at least one second remote UE (also referred to as the opposite remote UE) through the same relay UE. When the relay UE detects that the radio link to at least one second remote UE fails, it sends a notification message to the first remote UE, whereby the first remote UE can perform relevant operations when the radio link fails on some (one or more than one, not including all) or all (all) second remote UEs according to the notification message. The notification message may include identification information related to the radio link failure, and the identification information related to the radio link failure includes identification information related to at least one second remote UE with a failed radio link. Thus, the first remote UE can determine at least one second remote UE with a failed radio link according to the notification message, and then perform operations on the at least one second remote UE (part, not including all) or all (all) second remote UEs. When the first remote UE performs an operation on the at least one second remote UE, if the relay UE fails in its radio link to some of the second remote UEs, the communication of the second remote UEs whose radio links with the relay UE are normal will not be affected, thereby avoiding the service interruption time between the first remote UE and the second remote UEs that are still communicating normally, thereby improving the user experience. When the first remote UE performs relevant operations on all second remote UEs, the complexity of the behavior of the first remote UE can be reduced, making the behavior of the first remote UE simple. In addition, the notification message may also not include identification information related to the radio link failure. After receiving the notification message, the first remote UE performs relevant operations on all second remote UEs, making the behavior of the first remote UE simple.

[0205] The above embodiments are merely exemplary of the present invention, but the present invention is not limited thereto. Appropriate modifications may be made based on the above embodiments. For example, the above embodiments may be used alone, or one or more of the above embodiments may be combined.

[0206] It is worth noting that the above only describes the steps related to the present application, but the present application is not limited thereto. The above method of the present application may also include other steps, and the specific contents of these steps can be referred to the relevant art.

[0207] Embodiments of the third aspect

[0208] An embodiment of the present application provides a communication system, which can be referred to in Figure 2 or Figure 3. The communication system includes a first remote UE 201, a relay UE 203 and a second remote UE 202, wherein the number of the second remote UE 202 is at least one, for example, two second remote UEs 202-1 and 202-2 are shown in Figures 2 and 3.

[0209] In the embodiment of the present application, the first remote UE 201 is configured to execute the information receiving method in the first aspect of the present application, the content of which is incorporated herein and will not be repeated here;

[0210] In the embodiment of the present application, the relay UE 203 is configured to execute the information sending method in the first aspect of the present application, the content of which is incorporated herein and will not be repeated here;

[0211] In this embodiment of the present application, the second remote UE 202 is configured to communicate with the first remote UE 201 via the relay UE 203 .

[0212] In UE-to-UE relay, a remote UE communicates with at least one remote UE at the opposite end through the same relay UE. The relay UE detects the radio link failure (RLF) of the remote UE at the opposite end and sends a notification message to the remote UE indicating the failure of the radio link to at least one remote UE at the opposite end. As a result, the remote UE can perform relevant operations when the radio link fails on some (including one or more than one) or all (i.e., all) remote UEs at the opposite end according to the notification message.

[0213] Embodiments of the fourth aspect

[0214] An embodiment of the present application provides a terminal device.

[0215] Figure 10 is a schematic diagram of the structure of a terminal device according to an embodiment of the present application, which may be a remote terminal device. As shown in Figure 10 , terminal device 1000 may include a processor 1001 and a memory 1002. Memory 1002 stores data and programs and is coupled to processor 1001. It should be noted that this diagram is exemplary; other types of structures may be used to supplement or replace this structure to implement telecommunication or other functions.

[0216] For example, the processor 1001 may be configured to execute a program to implement the information receiving method as described in the embodiment of the first aspect, where the terminal device 1001 is, for example, a remote UE. The processor 1001 may be configured to perform the following operations: communicate with at least one second remote UE via a relay UE; receive a notification message sent by the relay UE; the notification message is used to indicate a failure of a radio link between the relay UE and the at least one second remote UE.

[0217] For another example, the processor 1001 may be configured to execute a program to implement the information sending method as described in the embodiment of the first aspect, where the terminal device 1001 is, for example, a relay UE. The processor 1001 may be configured to perform the following operations: communicate with a first remote UE and at least one second remote UE; and send a notification message to the first remote UE; the notification message is used to indicate a failure of a radio link between the relay UE and the at least one second remote UE.

[0218] As shown in Figure 10 , the terminal device 1000 may further include: a communication module 1003, an input unit 1004, a display 1005, and a power supply 1006. The functions of these components are similar to those in the prior art and are not described in detail here. It is worth noting that the terminal device 1000 does not necessarily include all of the components shown in Figure 10 , and these components are not essential. Furthermore, the terminal device 1000 may also include components not shown in Figure 10 , for which reference may be made to the relevant art.

[0219] An embodiment of the present application also provides a computer-readable program, wherein when the program is executed in a terminal device, the program enables the computer to execute the information receiving method described in the embodiment of the first aspect of the present application in the relay terminal device.

[0220] An embodiment of the present application also provides a computer-readable program, wherein when the program is executed in a terminal device, the program enables the computer to execute the information sending method described in the embodiment of the first aspect of the present application in the relay terminal device.

[0221] An embodiment of the present application also provides a storage medium storing a computer-readable program, wherein the computer-readable program enables a computer to execute the information receiving method described in the embodiment of the first aspect of the present application in a terminal device.

[0222] An embodiment of the present application also provides a storage medium storing a computer-readable program, wherein the computer-readable program enables a computer to execute the information sending method described in the embodiment of the first aspect of the present application in a terminal device.

[0223] The above devices and methods of the present application can be implemented by hardware or by a combination of hardware and software. The present application relates to such a computer-readable program that, when executed by a logic component, enables the logic component to implement the devices or components described above, or enables the logic component to implement the various methods or steps described above. The present application also relates to a storage medium for storing the above program, such as a hard disk, a magnetic disk, an optical disk, a DVD, a flash memory, etc.

[0224] The method / device described in conjunction with the embodiments of the present application can be directly embodied as hardware, a software module executed by a processor, or a combination of the two. For example, one or more of the functional block diagrams shown in the figure and / or one or more combinations of functional block diagrams can correspond to various software modules of the computer program flow or to various hardware modules. These software modules can respectively correspond to the various steps shown in the figure. These hardware modules can be implemented by solidifying these software modules, for example, using a field programmable gate array (FPGA).

[0225] The software module may be located in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, a hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art. A storage medium may be coupled to a processor so that the processor can read information from the storage medium and write information to the storage medium; or the storage medium may be an integral part of the processor. The processor and the storage medium may be located in an ASIC. The software module may be stored in the memory of the mobile terminal or in a memory card that can be inserted into the mobile terminal. For example, if the device (such as a mobile terminal) uses a large-capacity MEGA-SIM card or a large-capacity flash memory device, the software module may be stored in the MEGA-SIM card or the large-capacity flash memory device.

[0226] One or more of the functional blocks and / or one or more combinations of functional blocks described in the accompanying drawings may be implemented as a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA) or other programmable logic device, a discrete gate or transistor logic device, a discrete hardware component, or any appropriate combination thereof for performing the functions described in this application. One or more of the functional blocks and / or one or more combinations of functional blocks described in the accompanying drawings may also be implemented as a combination of computing devices, such as a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors in communication with a DSP, or any other such configuration.

[0227] The present application has been described above in conjunction with specific embodiments. However, those skilled in the art should understand that these descriptions are merely illustrative and are not intended to limit the scope of protection of the present application. Those skilled in the art may make various modifications and variations to the present application based on the spirit and principles of the present application, and such modifications and variations are also within the scope of the present application.

[0228] Regarding the implementation methods including the above embodiments, the following additional notes are also disclosed:

[0229] 1. A remote UE, comprising a memory and a processor, wherein the memory stores a computer program, and the processor is configured to execute the computer program to implement any information receiving method described in the embodiments of the present application.

[0230] 2. A relay UE, comprising a memory and a processor, wherein the memory stores a computer program, and the processor is configured to execute the computer program to implement any information sending method described in the embodiments of the present application.

Claims

1. An information receiving device, applied to a first remote UE, the device comprising: A first communication unit, configured to communicate with at least one second remote UE via a relay UE; The first receiving unit is used to receive a notification message sent by the relay UE, where the notification message is used to indicate that a radio link between the relay UE and at least one of the second remote UEs has failed.

2. The device according to claim 1, wherein: The notification message includes identification information related to the radio link failure.

3. The device according to claim 2, wherein: The identification information includes at least one of the following information: L2 identifier of the second remote UE; A local identifier of a second remote UE; A pair of an L2 identifier of a first remote UE and an L2 identifier of a second remote UE; and A pair of a local identifier of a first remote UE and a local identifier of a second remote UE.

4. The device according to claim 3, wherein: The local identifier of the first remote UE and / or the local identifier of the second remote UE are allocated by the relay UE.

5. The device according to claim 3, wherein: During data transmission between the first remote UE and the second remote UE, the local identifier of the first remote UE and the local identifier of the second remote UE are included in the SRAP header.

6. The device according to claim 2, wherein: The device also includes a first operating unit, which is used to: perform relevant operations on the at least one second remote UE.

7. The device according to claim 6, wherein: The related operations include at least one of the following: Indicating information of the at least one second remote UE to an upper layer, the information comprising at least one of the following information: an L2 identifier of the second remote UE, a PC5 unicast link identifier (unicast link identifier) ​​between the first remote UE and the second remote UE, and a pair of an L2 identifier of the first remote UE and an L2 identifier of the second remote UE; Instructing an upper layer to trigger reselection of a relay UE for the at least one second remote UE; Determining that the relay UE detects a radio link failure for the at least one second remote UE; Instructing an upper layer to release the PC5-RRC connection with the at least one second remote UE; releasing the PC5-RRC connection with the at least one second remote UE; When the first remote UE is in an RRC connected state, executing a sidelink UE information process; releasing all SRBs and / or DRBs between the remote UE and the second remote UE; Indicate to an upper layer that a PC5 RLF for the second remote UE is received from the relay UE; Maintain connection with a second remote UE that communicates with the first remote UE via the relay UE and whose radio link with the relay UE has not failed.

8. The device according to claim 7, wherein: The upper layer includes a V2X layer or a NAS layer.

9. The device according to claim 1, wherein: The apparatus further includes a second operating unit, which is configured to perform relevant operations on all second remote UEs that communicate with the first remote UE via the relay UE.

10. The device according to claim 9, wherein: The related operations include at least one of the following: Indicating to an upper layer information about all the second remote UEs, the information comprising at least one of the following information: an L2 identifier of the second remote UE, a PC5 unicast link identifier between the first remote UE and the second remote UE, and a pair of an L2 identifier of the first remote UE and an L2 identifier of the second remote UE; Instructing an upper layer to trigger reselection of a relay UE for all the second remote UEs; Determining that the relay UE detects a radio link failure for all the second remote UEs; Instructing an upper layer to release the PC5-RRC connection with all the second remote UEs; Releasing the PC5-RRC connections with all the second remote UEs; When the first remote UE is in an RRC connected state, executing a sidelink UE information process; releasing all SRBs and / or DRBs between the second remote UEs; Indicate to an upper layer that the PC5 RLF for all the second remote UEs is received from the relay UE.

11. The device according to claim 1, wherein: The notification message is sent via a PC5-RRC message.

12. The device according to claim 1, wherein: The wireless link is a PC5 wireless link or a PC5 unicast link.

13. An information sending device, applied to a relay UE, the device comprising: A second communication unit, configured to communicate with the first remote UE and at least one second remote UE; A first sending unit is configured to send a notification message to the first remote UE, where the notification message is used to indicate that a radio link between the relay UE and at least one of the second remote UEs has failed.

14. The device according to claim 13, wherein: The notification message includes identification information related to the radio link failure.

15. The device according to claim 14, wherein: The identification information includes at least one of the following information: L2 identifier of the second remote UE; A local identifier of a second remote UE; A pair of an L2 identifier of a first remote UE and an L2 identifier of a second remote UE; and A pair of a local identifier of a first remote UE and a local identifier of a second remote UE.

16. The device according to claim 15, wherein: The local identifier of the first remote UE and / or the local identifier of the second remote UE are allocated by the relay UE.

17. The device according to claim 15, wherein: During data transmission between the first remote UE and the second remote UE, the local identifier of the first remote UE and the local identifier of the second remote UE are included in the SRAP header.

18. The device according to claim 13, wherein: The device also includes: a detection unit, configured to detect a wireless link between a second remote UE communicating with the first remote UE via the relay UE; Furthermore, when the first sending unit detects that a radio link failure occurs between the first sending unit and at least one of the second remote UEs, the first sending unit sends the notification message to the first remote UE.

19. The device according to claim 13, wherein: The notification message is sent via a PC5-RRC message.

20. A communication system, characterized in that: The communication system comprises: A first remote UE, wherein the first remote UE comprises the information receiving device according to any one of claims 1 to 12; A relay UE, the relay UE comprising the information sending device according to any one of claims 13 to 19; and At least one second remote UE, wherein the at least one second remote UE is configured to communicate with the first remote UE via the relay UE.

Images