User equipment, base station and method thereof

Abstract

According to the present invention, a user equipment, a base station and a method thereof are provided. The method executed by user equipment UE comprises the following steps: for the UE which is in an RRC inactive state and is added with one or more MBS multicast services, judging whether an MRB established for receiving an MBS multicast session in the RRC inactive state exists or not; and if the MRB established for receiving the MBS multicast session in the RRC inactive state exists, detecting or receiving the multicast MCCH.

Description

Technical Field

[0001] The present invention relates to the field of wireless communication technology, and more particularly, to user equipment, a base station and a method thereof. Background Art

[0002] A research project SI (see SP-190625 for details) on the improvement of the 5G multicast broadcast service architecture has been approved. One of the goals of this SI (called Goal A) is to support universal MBS services in 5GS. Use cases that can benefit from this feature include (but are not limited to) public safety, V2X applications, transparent IPv4 / IPv6 multicast transmission, IPTV, wireless software transmission, group communication and IoT applications. Accordingly, at the 3rd Generation Partnership Project (3GPP) RAN#86 plenary meeting, a work item on NR multicast and broadcast service (NR MBS) was proposed and approved (see non-patent literature: RP-193248: New WID: NR Multicast and Broadcast Service). This work item aims to provide support for Goal A in RAN. The goals of this work item have been basically achieved, and the specific description of the relevant solutions can be found in 3GPP Release 17 technical documents, such as TS38.300-h30, TS38.331-h30, TS38.321-h30, etc. At the 3GPP RAN#94 plenary meeting, a work item named Enhanced NR Broadcast Multicast was approved (see non-patent document: RP-213568: New WID: Enhancements of NR Multicast and Broadcast Services). This work item aims to further enhance the MBS broadcast multicast of Release 17, one of its goals is to support user equipment to receive MBS multicast services / sessions in the RRC inactive state.

[0003] The present invention discusses the related issues involved in RAN supporting user equipment to receive MBS multicast services / sessions in an RRC inactive state. Summary of the invention

[0004] In order to solve the above problem, the present invention provides a user equipment, a base station and a method thereof, so that a UE in an RRC_INACTIVE state and capable of receiving an MBS multicast service in the RRC_INACTIVE state can effectively detect or receive a multicast MCCH.

[0005] In order to achieve the above-mentioned purpose, according to the present invention, a method executed by a user equipment UE is proposed, comprising: for a UE that is in an RRC inactive state and has joined one or more MBS multicast services, determining whether there is an MRB established for the purpose of receiving an MBS multicast session in the RRC inactive state; and if there is an MRB established for the purpose of receiving an MBS multicast session in the RRC inactive state, detecting or receiving a multicast MCCH.

[0006] Preferably, the method further comprises: if the MRB does not exist or is not established, not detecting or receiving the multicast MCCH.

[0007] In addition, according to the present invention, a method performed by a user equipment UE is proposed, comprising: receiving an RRC release message from a base station; and in a case where the received RRC release message includes information for indicating a configuration in an RRC inactive state and a PTM configuration of an MBS multicast session received in an RRC inactive state, performing at least one of the following operations: if the MBS multicast session corresponding to the PTM configuration is indicated as being in an active state, applying the PTM configuration and performing MBS multicast reception in an RRC inactive state; if the MBS multicast session corresponding to the PTM configuration is indicated as being in an inactive state, applying the PTM configuration but not performing MBS multicast reception in an RRC inactive state; if the MBS multicast session corresponding to the PTM configuration is indicated as being in an active state, Use the PTM configuration and perform MBS multicast reception in the RRC non-activated state. If the MBS multicast session corresponding to the PTM configuration is indicated to be in the non-activated state, establish the corresponding MRB according to the PTM configuration but do not perform MBS multicast reception in the RRC non-activated state; if the MBS multicast session corresponding to the PTM configuration is indicated to be in the activated state, apply the PTM configuration and perform MBS multicast reception in the RRC non-activated state. If the MBS multicast session corresponding to the PTM configuration is indicated to be in the non-activated state, save the PTM configuration; if the MBS multicast session corresponding to the PTM configuration is indicated to be in the non-activated state, apply the PTM configuration or save the PTM configuration, and / or detect or receive multicast MCCH; and detect or receive multicast MCCH.

[0008] In addition, according to the present invention, a method performed by a user equipment UE is proposed, comprising: for a UE that is in an RRC inactive state and has joined one or more MBS multicast services, determining whether there is an MRB established for the purpose of receiving an MBS multicast session in the RRC inactive state, or whether one or more MBS multicast sessions that have been joined are indicated as being in an active state, or whether a PTM configuration of an MBS multicast session indicated as being in an inactive state is saved, or whether all PTM configurations of MBS multicast sessions received in the RRC_INACTIVE state that are saved are indicated as being in an inactive state, or whether there is a UE that has joined one or more MBS multicast services in the RRC_INACTIVE state. The multicast MCCH is detected or received if there is an MRB established for the purpose of receiving an MBS multicast session in an RRC inactive state, or one or more joined MBS multicast sessions are indicated as being in an active state, or a PTM configuration of an MBS multicast session indicated as being in an inactive state is saved, or all the saved PTM configurations of MBS multicast sessions received in the RRC_INACTIVE state are indicated as being in an inactive state, or there is an MRB established for the purpose of receiving an MBS multicast session in the RRC_INACTIVE state and all the MBS multicast sessions are in an inactive state.

[0009] Preferably, the method further comprises: if there is no PTM configuration for the MBS multicast session that has been joined and indicated as being in an active state and the MBS multicast session that has been joined and indicated as being in an inactive state, not detecting or not receiving the multicast MCCH.

[0010] In addition, according to the present invention, a method performed by a user equipment UE is proposed, comprising: for a UE that is in an RRC-inactive state and has joined one or more MBS multicast services, determining whether it is configured as a special UE or a UE that assumes a leader role in a group, or whether it is configured to detect MCCH, or whether it is configured to be able to receive MBS multicast sessions in an RRC-inactive state, or whether it is configured not to need to detect MCCH, or whether it is configured not to be able to receive MBS multicast sessions in an RRC-inactive state; and if it is not configured as a special UE or a UE that assumes a leader role in a group, or is configured to detect MCCH, or is configured to be able to receive MBS multicast sessions in an RRC-inactive state, or is not configured not to need to detect MCCH, or is not configured not to be able to receive MBS multicast sessions in an RRC-inactive state, detecting or receiving the multicast MCCH.

[0011] Preferably, the method also includes: in a case where the PTM configuration of the MBS multicast session indicated by the TMGI is obtained through the multicast MCCH, applying the PTM configuration and performing MBS multicast reception in the RRC inactive state; and in a case where the PTM configuration of the MBS multicast session indicated by the TMGI is not obtained through the multicast MCCH, but the UE locally saves the PTM configuration of the MBS multicast session indicated by the TMGI, applying the PTM configuration and performing MBS multicast reception in the RRC inactive state.

[0012] In addition, according to the present invention, a user equipment is proposed, comprising: a processor; and a memory storing instructions, wherein the instructions execute the above method when executed by the processor.

[0013] In addition, according to the present invention, a method performed by a base station is proposed, wherein the base station communicates with a user equipment UE, and the method comprises: when the multicast MCCH information changes, notifying the UE of the change of the multicast MCCH information; and sending the changed multicast MCCH information to the UE, wherein the multicast MCCH information is used to enable the UE to obtain or update the MRB established for receiving an MBS multicast session in an RRC inactive state or the PTM configuration of the MBS multicast session, or to enable the UE to obtain or update the PTM configuration of an MBS multicast session received in an RRC inactive state and indicated as being in an inactive state.

[0014] In addition, according to the present invention, a base station is proposed, comprising: a processor; and a memory storing instructions, wherein the instructions execute the above method when executed by the processor.

[0015] Effects of the Invention

[0016] According to the present invention, a UE in an RRC_INACTIVE state and capable of receiving an MBS multicast service in the RRC_INACTIVE state can effectively detect or receive a multicast MCCH. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The above and other features of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which:

[0018] Figure 1 is a flowchart showing a method executed by a user equipment according to embodiment 1 of the present invention.

[0019] Figure 2 is a flowchart showing a method executed by a user equipment according to embodiment 2 of the present invention.

[0020] Figure 3is a flowchart showing a method executed by a user equipment according to embodiment 3 of the present invention.

[0021] Figure 4 is a flowchart showing a method executed by a user equipment according to embodiment 4 of the present invention.

[0022] Figure 5 is a block diagram schematically showing a user equipment involved in the present invention.

[0023] Figure 6 is a block diagram schematically showing a base station involved in the present invention. DETAILED DESCRIPTION

[0024] The present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the present invention should not be limited to the specific embodiments described below. In addition, for the sake of simplicity, detailed descriptions of known technologies that are not directly related to the present invention are omitted to prevent confusion in understanding the present invention.

[0025] The following describes some terms involved in the present invention. For specific meanings of the terms, refer to the latest relevant 3GPP documents, such as TS38.300-h30, TS38.321-h30, TS38.323-h30, TS38.331-h30, etc. In addition, the embodiments of the present invention are described by taking broadcast / multicast services as an example, but the embodiments of the present invention are not limited to broadcast / multicast services and can also be applied to other application scenarios.

[0026] UE: User Equipment.

[0027] RRC: Radio Resource Control.

[0028] RRC_CONNECTED: RRC connected state.

[0029] RRC_INACTIVE: RRC inactive state.

[0030] RRC_IDLE: RRC idle state.

[0031] RAN: Radio Access Network.

[0032] NR: New RAT, new radio access technology.

[0033] MBS: Multicast / Broadcast Services. Multicast can also be called groupcast.

[0034] AS: Access Stratum, access layer or access layer.

[0035] NAS: Non Access Stratum, non-access layer or non-access layer.

[0036] RB: Radio Bearer. DRB is a data radio bearer.

[0037] MRB: MBS radio bearer, i.e., a radio bearer that is configured for MBS delivery. MRB is divided into multicast MRB and broadcast MRB. Multicast MRB is a radio bearer configured for MBS multicast transmission, while broadcast MRB is a radio bearer configured for MBS broadcast transmission.

[0038] TMGI: Temporary Mobile Group Identity, used to identify an MBS session.

[0039] RNTI: Radio Network Temporary Identifier, wireless network temporary identifier.

[0040] PTM: Point to Multipoint, a delivery method for MBS services. In the PTM delivery method, the gNB delivers a single copy of MBS data packets to a set of UEs. UEs use G-RNTI or G-CS-RNTI to receive PTM transmissions. For example, the base station uses the group common physical downlink control channel PDCCH using G-RNTI to schedule the same group common physical downlink shared channel PDSCH using G-RNTI.

[0041] PTP: Point to Point, a delivery method for MBS services. In the PTP delivery method, the RAN node delivers separate copies of multiple MBS data packets to each UE individually (gNB individually deliversseparate copies of MB S data packets to each UEs independently). For example, the base station schedules the UE-specific PDCCH scrambled by the UE-specific RNTI and the UE-specific PDSCH scrambled by the same UE-specific RNTI.

[0042] G-RNTI: Group RNTI, group RNTI, used to scramble the scheduling and transmission of PTM for one or more MBS multicast services.

[0043] G-CS-RNTI: Group configuration scheduling RNTI, used to scramble the semi-static scheduling SPS group common physical downlink shared channel PDSCH of one or more MBS multicast services and activate / deactivate the SPS group common PDSCH.

[0044] MTCH: MBS Traffic Channel, MBS traffic channel, is a PTM downlink channel used to transmit MBS data of a multicast session or a broadcast session from the network to the UE. Unless otherwise specified, the MTCH involved in the embodiments of the present disclosure refers to a multicast MTCH used to transmit an MBS multicast session.

[0045] MCCH:MBS Control Channel, MBS control channel, is a PTM downlink channel used for transmitting MBS broadcast or MBS multicast control informationassociated to one or several MTCH(s)from the network to the UE. MCCH includes broadcast MCCH and multicast MCCH.

[0046] The RRC recovery request message RRCResumeRequest or RRCResumeRequest1 is used to request the recovery of a suspended RRC connection or to perform a RAN-based notification area RNA update. When the UE initiates an RRC connection recovery request, if SIB1 contains the useFullResumeID field, the RRCResumeRequest1 message is used and the resumeIdentity field in the RRCResumeRequest1 message is set to the fullI-RNTI stored by the UE, otherwise RRCResumeRequest is used and the resumeIdentity field in the RRCResumeRequest message is set to the stored shortI-RNTI. The RRC release message RRCRelease is used to command the release of an RRC connection or to suspend an RRC connection. The RRC reconfiguration message RRCReconfiguration is used to command the modification of the RRC connection. The RRC recovery message RRCResume is used to recover a suspended RRC connection. In the present disclosure, the useFullResumeID field indicates the resume identifier and resume request message used. When the field is included in SIB1, fullI-RNTI and RRCResumeRequest1 message are used. When the field is not included in SIB1, shortI-RNTI and RRCResumeRequest message are used. ShortI-RNTI uses fewer bits than I-RNTI-Value to identify the suspended UE context of a UE in an RRC inactive state.

[0047] In the present invention, network, base station and RAN can be used interchangeably, and the network can be a long-term evolution LTE network, a NR network, an enhanced long-term evolution eLTE network, or other networks defined in subsequent evolution versions of 3GPP.

[0048] At present, NR MBS services include MBS broadcast (also known as MBS broadcast session or broadcast MBS or MBS broadcast service) and MBS multicast (also known as MBS multicast session or multicast MBS or MBS multicast service). MBS broadcast provides a downlink-only MBS transmission mode for services with low quality of service QoS, so that UEs in RRC connected state, RRC idle state and RRC inactive state can receive the MBS service. The UE obtains the MBS broadcast configuration information broadcast by the network through the MBS control channel MCCH. In 3GPP version 17, the UE needs to establish an RRC connection with the base station before receiving the MBS multicast service (i.e., MBS multicast session), and then the base station configures the resources for receiving the MBS multicast service for the UE through dedicated RRC signaling (also known as RRC message, such as RRC reconfiguration message). The MBS radio bearer MRB for receiving these MBS multicast services is also configured for the UE by the base station through dedicated RRC signaling. Only UEs in the RRC connected state and configured with MRB can receive the corresponding MBS multicast service.

[0049] In version 17, it is not supported for UE to receive MBS multicast sessions in RRC inactive state. Therefore, when an MBS multicast session is activated by the core network or the base station has MBS multicast session data to send, the network supporting MBS multicast notifies the UE in RRC idle state or RRC inactive state through a group notification mechanism. Upon receiving the group notification, the UE that has joined or is interested in the MBS multicast session establishes or restores an RRC connection with the network to receive the corresponding MBS multicast session. The group notification is addressed with P-RNTI on the physical downlink control channel PDCCH, and the UE monitors the paging channel. The paging message used for group notification contains the MBS session identifier TMGI, which is used to page all UEs that have joined the relevant MBS multicast session and are in RRC idle state or RRC inactive state. In other words, the base station does not page the UE individually (for the purpose of the UE receiving the MBS multicast session).

[0050] In version 18, UE is supported to receive MBS multicast sessions in RRC inactive state. For MBS multicast sessions received in RRC inactive state, the base station can provide or configure PTM configuration information (also called configuration information of MBS multicast session or PTM configuration of MBS multicast session) for UE to receive the MBS multicast session through dedicated RRC signaling (e.g., RRCRelease message) or through multicast MBS control channel MCCH (i.e., multicast MCCH). The information required to obtain multicast MCCH (or multicast MCCH configuration) can be configured for UE through dedicated RRC signaling or system information block (denoted as SIBx), that is, SIBx contains the information required to obtain the multicast MCCH configuration of MBS multicast received in RRC inactive state. The PTM configuration information may include the configuration information of the MRB corresponding to the MBS multicast session and / or the identifier TMGI of the MBS multicast session and its corresponding G-RNTI / G-CS-RNTI and / or DRX and other configuration information fields. The multicast MCCH is a PTM downlink channel used for transmitting control information of MB S multicast session associated to one or several MTCH(s)from the network to the UE in RRC_INACTIVE state. For an MBS multicast session received in the RRC_INACTIVE state, the MBS multicast session being in an active state or being activated in the present disclosure means that the MBS multicast session is in progress or about to start or the UE starts to receive the MBS multicast session. The network can indicate to the UE that the MBS multicast is activated through RRC signaling (e.g., RRC release message) or through a paging message (e.g., including the TMGI of the MBS multicast session in a paging message indicates that the MBS multicast session is activated), and the UE starts to receive the MBS multicast session after receiving the indication. In the present disclosure, the MBS multicast session being in an inactive state or being deactivated means that the MBS multicast session has ended or data transmission has been suspended or the UE has stopped receiving the MBS multicast session.The network may notify the UE through a multicast MCCH message (for example, if the PTM configuration of the MBS multicast session does not appear in the multicast MCCH message, it indicates that the MBS multicast session is deactivated, and an indication identifier is associated with each MBS multicast session to explicitly indicate that the MBS multicast session is deactivated) or through the PDCCH that schedules the multicast MCCH (or multicast MCCH message), for example, using 1 bit in the DCI of the PDCCH to indicate that the MBS multicast is deactivated or data transmission is suspended. After receiving the indication, the UE stops receiving the MBS multicast session.

[0051] Each MBS multicast session is identified by a TMGI and is associated with a G-RNTI or G-CS-RNTI. The UE receives the MBS multicast session by monitoring the G-RNTI or G-CS-RNTI associated with the MBS multicast session. For MBS multicast, the MAC entity may be configured by RRC with a DRX functionality per G-RNTI or per G-CS-RNTI that controls the UE′s PDCCH monitoring activity for the MACentity′s G-RNTI(s)and G-CS-RNTI(s) respectively.

[0052] Release 18 supports a UE in an RRC inactive state to receive an MBS multicast session. The present disclosure considers when a UE in an RRC_INACTIVE state that can receive an MBS multicast service in the RRC_INACTIVE state starts to detect or receive a multicast MCCH.

[0053] In order to solve at least part of the above problems, the present disclosure provides corresponding embodiments. Specific embodiments are listed below to illustrate the processing method of the present invention. In addition, the embodiments listed below are only examples and are not intended to limit the present invention.

[0054] Example 1

[0055] Figure 1 is a flowchart showing a method executed by a user equipment according to embodiment 1 of the present invention.

[0056] like Figure 1 As shown, in step 101, for a UE in the RRC_INACTIVE state and joined to one or more MBS multicast services, it is determined whether there is an MRB established in the UE for the purpose of receiving an MBS multicast session in the RRC_INACTIVE state, wherein the MBS multicast session may be in an active state or an inactive state.

[0057] In step 103, if there is an MRB established for the purpose of receiving an MBS multicast session in the RRC_INACTIVE state in the UE, the UE detects or receives a multicast MCCH, the purpose of which is to obtain or update the MRB established for receiving an MBS multicast session in the RRC_INACTIVE state or the PTM configuration of the MBS multicast session. Optionally, if the UE in the RRC inactive state joins one or more MBS multicast services, but the MRB of the joined MBS multicast session does not exist or is not established in the UE, the UE does not detect or receive the multicast MCCH. The UE detecting or receiving the multicast MCCH may refer to the UE acquiring or detecting a change notification of the multicast MCCH information. When the network changes the multicast MCCH information, the network notifies the UE by scheduling the PDCCH of the multicast MCCH (or the multicast MCCH message), for example, indicating it with 1 bit in the DCI of the PDCCH. When the UE receives the notification, the UE acquires the new or modified multicast MCCH information. The multicast MCCH information may be an MBS multicast configuration message or the information contained therein. The MBS multicast configuration message contains the control information applicable for MBS multicast services transmitted via multicast-inactive MRBs for RRC_INACTIVE UEs.

[0058] Example 2

[0059] Figure 2 is a flowchart showing a method executed by a user equipment according to embodiment 2 of the present invention.

[0060] like Figure 2 As shown, in step 201, the UE receives an RRC release message from a base station.

[0061] In step 203, if the RRC release message carries the suspendConfig field for indicating the configuration in the RRC inactive state, and the RRC release message carries the PTM configuration of the MBS multicast session received in the RRC inactive state, the UE performs at least one of the following operations:

[0062] Operation 1-1: If the MBS multicast session corresponding to the PTM configuration carried in the RRC release message is indicated as being in an activated state, the PTM configuration is applied and MBS multicast reception in an RRC inactive state is performed; if the MBS multicast session corresponding to the PTM configuration carried in the RRC release message is indicated as being in an inactive state, the PTM configuration is applied but MBS multicast reception in RRC_INACTIVE is not performed. It should be noted that, in the embodiment of the present disclosure, for an MBS multicast session indicated as being in an inactive state, the application of the PTM configuration does not include the DRX configuration information contained therein, and the DRX configuration information takes effect only when the MBS multicast session indicated as being in an inactive state is activated.

[0063] Operation 1-2: If the MBS multicast session corresponding to the PTM configuration carried in the RRC release message is indicated to be in an activated state, the PTM configuration is applied and the MBS multicast reception in the RRC inactive state is performed; if the MBS multicast session corresponding to the PTM configuration carried in the RRC release message is indicated to be in an inactive state, the corresponding MRB is established according to the PTM configuration but the MBS multicast reception in the RRC inactive state is not performed.

[0064] Operation 1-3: If the MBS multicast session corresponding to the PTM configuration carried in the RRC release message is indicated to be in an activated state, apply the PTM configuration and perform MBS multicast reception in the RRC inactive state; if the MBS multicast session corresponding to the PTM configuration carried in the RRC release message is indicated to be in an inactive state, save the PTM configuration.

[0065] Operation 1-4: If the MBS multicast session corresponding to the PTM configuration carried in the RRC release message is indicated as being in an inactive state (or all MBS multicast sessions corresponding to the PTM configuration carried are indicated as being in an inactive state), the PTM configuration is applied or saved, and / or the multicast MCCH is detected or received. The UE detecting or receiving the multicast MCCH may refer to the UE obtaining or detecting a notification of a change in the multicast MCCH information, so that the UE can obtain the updated multicast MCCH information in a timely manner. When the UE receives the notification, the UE obtains the new or modified multicast MCCH information.

[0066] Operation 1-5: The UE detects or receives the multicast MCCH, and the MBS multicast session may be indicated as being in an active state or an inactive state.

[0067] Optionally, if the RRC release message does not include a PTM configuration indicating an MBS multicast session to which the UE in the activated state has joined, the UE detects or receives the multicast MCCH.

[0068] It should be noted that, in the implementation of the present disclosure, the indication of whether the MBS multicast session is in an activated state may be carried in an RRC release message, and the RRC release message may indicate that an MBS multicast session is in an activated state or an inactivated state, or may only indicate an MBS multicast session in an activated state, and those MBS multicast sessions that are not indicated as being in an activated state are implicitly indicated as being in an inactivated state. It may also only indicate an MBS multicast session in an inactivated state, and accordingly, those MBS multicast sessions that are not indicated as being in an inactivated state are implicitly indicated as being in an activated state.

[0069] In the embodiment of the present disclosure, if not specifically stated, the application of PTM configuration may include establishing a corresponding MRB according to the PTM configuration and / or configuring the DRX for the MAC entity of the UE if the PTM configuration contains DRX configuration information. The execution of MBS multicast reception in the RRC inactive state in the embodiment of the present disclosure refers to receiving DL-SCH using the G-RNTI (or the G_RNTI of the MBS session indicated by the TMGI) and / or mtch-SchedulingInfo corresponding to the TMGI (i.e., the TMGI of the MBS multicast session to be received) or using the g-RNTI (or the G_RNTI of the MBS session indicated by the TMGI) and / or mtch-SchedulingInfo corresponding to the TMGI to receive DL-SCH on a cell that receives an MBS multicast configuration message (an MBS multicast configuration message received to establish the MRB corresponding to the TMGI). The mtch-SchedulingInfo indicates information related to the corresponding MBS multicast session or the DRX configuration for scheduling MTCH. In the embodiment of the present disclosure, unless otherwise specified, not performing MBS multicast reception in the RRC inactive state includes not indicating to the lower layer or not starting the DRX corresponding to the MBS multicast session indicated as being in the inactive state. In other words, the lower layer (e.g., MAC) does not detect the G-RNTI corresponding to the MBS multicast session indicated as being in the inactive state based on the DRX.

[0070] Example 3

[0071] Figure 3 is a flowchart showing a method executed by a user equipment according to embodiment 3 of the present invention.

[0072] like Figure 3 As shown, in step 301, for a UE that is in the RRC_INACTIVE state and joined to one or more MBS multicast services, it is determined whether there is an MRB established in the UE for the purpose of receiving an MBS multicast session in the RRC_INACTIVE state, or whether one or more MBS multicast sessions that the UE has joined are indicated as being in an active state, or whether the UE saves a PTM configuration of an MBS multicast session that is indicated as being in an inactive state, or whether the PTM configurations of the MBS multicast sessions received in the RRC_INACTIVE state saved by the UE are all indicated as being in an inactive state, or whether there is an MRB established in the UE for the purpose of receiving an MBS multicast session in the RRC_INACTIVE state and the MBS multicast sessions are all in an inactive state.

[0073] In step 303, if there is an MRB established in the UE for the purpose of receiving an MBS multicast session in the RRC_INACTIVE state, or one or more MBS multicast sessions that the UE has joined are indicated as being in an active state, or the UE saves a PTM configuration of an MBS multicast session indicated as being in an inactive state, or the PTM configurations of the MBS multicast sessions received in the RRC_INACTIVE state saved by the UE are all indicated as being in an inactive state, or there is an MRB established in the UE for the purpose of receiving an MBS multicast session in the RRC_INACTIVE state and the MBS multicast sessions are all in an inactive state, the UE detects or receives a multicast MCCH for the purpose of acquiring or updating the PTM configuration of the MBS multicast session received in the RRC_INACTIVE state and indicated as being in an inactive state. Optionally, if the UE in the RRC inactive state joins one or more MBS multicast services, but there is no PTM configuration of the MBS multicast session that has been joined and indicated as activated (i.e., in the active state) and the MBS multicast session that has been joined and indicated as in the inactive state (i.e., in the inactive state) in the UE, the UE does not detect or receive the multicast MCCH. The network can configure, for each MBS multicast session that the UE has joined or its corresponding TMGI, whether the UE is a special UE or whether it assumes a leader role in a group or whether it detects MCCH or whether it can receive MBS services under RRC_INACTIVE. At this time, it can be stipulated that the UE does not detect or receive the multicast MCCH only when all MBS multicast sessions that the UE has joined or their corresponding TMGIs are respectively configured as special UEs or assume a leader role in a group or do not detect MCCH or cannot receive MBS services under RRC_INACTIVE. In other words, for all MBS multicast sessions or their corresponding TMGIs that the UE has joined, the UE detects or receives the multicast MCCH only if there is at least one MBS multicast session or its corresponding TMGI that is configured not to be a special UE or not to assume a leader role in the group or to detect MCCH or to be able to receive MBS services under RRC_INACTIVE. The special UE described in the present disclosure refers to a UE that is not allowed to receive MBS multicast sessions under RRC_INACTIVE, even if the UE has the ability to receive MBS multicast sessions under RRC_INACTIVE. It is possible to configure or determine whether the UE is a special UE for each MBS multicast session or TMGI, and it is also possible to configure or stipulate that the special UE cannot receive any MBS multicast session under RRC_INACTIVE.

[0074] Example 4

[0075] Figure 4 is a flowchart showing a method executed by a user equipment according to embodiment 4 of the present invention.

[0076] like Figure 4 As shown, in step 401, for a UE that is in the RRC_INACTIVE state and joined to one or more MBS multicast services, it is determined whether the UE is configured as a special UE or a UE that assumes a leader role in a group, or whether the UE is configured to detect MCCH, or whether the UE is configured to receive MBS multicast sessions in the RRC_INACTIVE state, or whether the UE is configured not to detect MCCH, or whether the UE is configured not to receive MBS multicast sessions in the RRC_INACTIVE state.

[0077] In step 403, if the UE is not configured as a special UE or is not configured as a UE that assumes a leader role in a group, or the UE is configured to detect MCCH, or the UE is configured to receive an MBS multicast session in the RRC_INACTIVE state, or the UE is not configured not to need to detect MCCH, or the UE is not configured not to receive an MBS multicast session in the RRC_INACTIVE state, the UE detects or receives the multicast MCCH. The network can configure whether the UE is a special UE or assumes a leader role in a group or detects MCCH or whether it can receive MBS services in the RRC_INACTIVE state through RRC signaling (e.g., an RRC release message or an RRC reconfiguration message).

[0078] Example 5

[0079] A UE in RRC_INACTIVE receives a paging message from a base station. If the UE has joined one or more MBS sessions indicated by TMGIs contained in the pagingGroupList field in the paging message, and further, if the MBS sessions indicated by the TMGIs are all indicated in the paging message as being receivable in the RRC_inactive state, optionally, if the UE is also configured to receive an MBS multicast session in RRC_INACTIVE (the execution order of other judgment conditions except the first judgment condition is changeable), the UE performs one of the following operations:

[0080] Operation 5-1, the UE detects the multicast MCCH and obtains the multicast MCCH message (or the UE obtains the PTM configuration of the MBS multicast session indicated by the TMGI from the multicast MCCH message); if the UE obtains the PTM configuration, the PTM configuration is applied and the MBS multicast reception is performed in the RRC inactive state; if the PTM configuration of the MBS multicast session indicated by the TMGI is not obtained, but the UE locally saves the PTM configuration of the MBS multicast session indicated by the TMGI (for example, the PTM configuration is included in the most recently received RRC release message), the PTM configuration is applied and the MBS multicast reception is performed in the RRC inactive state; otherwise (that is, the PTM configuration of the MBS multicast session indicated by the TMGI is neither obtained from the MCCH nor carried in the most recently received RRC release message), the UE starts the RRC connection recovery process.

[0081] Operation 5-2, the UE determines whether the MRB of the MBS multicast session indicated by the TMGI has been established or whether the PTM configuration of the MBS multicast session is locally saved (i.e., whether it is carried in the most recently received RRC release message); if the MRB has been established or the PTM configuration of the MBS multicast session is locally saved, the MBS multicast reception is performed in the RRC inactive state; otherwise, the multicast MCCH is detected and the multicast MCCH message is obtained (or the UE obtains the PTM configuration of the MBS multicast session indicated by the TMGI from the multicast MCCH message). ), if the UE obtains the PTM configuration, it applies the PTM configuration and performs MBS multicast reception under RRC inactive state; if the MRB of the MBS multicast session, the UE does not locally save the PTM configuration of the MBS multicast session, and does not obtain the PTM configuration of the MBS multicast session from MCCH (that is, the MRB of the MBS multicast session indicated by the TMGI is not established, and its PTM configuration is neither obtained from MCCH nor carried in the most recently received RRC release message), the UE starts the RRC connection recovery process.

[0082] The UE initiates the RRC connection recovery process to recover a suspended RRC connection or to start small data transmission in an RRC inactive state. During this process, the UE will generate an RRC recovery request message and receive a response message such as an RRC recovery message or an RRC release message from the base station.

[0083] In the embodiment of the present disclosure, the pagingGroupList includes one or more TMGIs (i.e., a TMGI list). The MCCH message is an MBS multicast configuration message transmitted on a multicast MCCH and sent by the network to the UE, and contains control information applicable for MBS multicast services transmitted via multicast-inactive MRBs (i.e., sessions) for UEs in RRC_INACTIVE to receive MBS multicast sessions established under RRC_INACTIVE.

[0084] [Modifications]

[0085] Next, use Figure 5 A user equipment as a variation example that can execute the method executed by the user equipment described in detail above of the present invention is described.

[0086] Figure 5 It is a block diagram showing a user equipment UE involved in the present invention.

[0087] like Figure 5 As shown, the user equipment UE50 includes a processor 501 and a memory 502. The processor 501 may include, for example, a microprocessor, a microcontroller, an embedded processor, etc. The memory 502 may include, for example, a volatile memory (such as a random access memory RAM), a hard disk drive (HDD), a non-volatile memory (such as a flash memory), or other memories, etc. The memory 502 stores program instructions. When the instructions are executed by the processor 501, the above method performed by the user equipment described in detail in the present invention may be executed.

[0088] Next, use Figure 6 A base station that can execute the method executed by the base station described above of the present invention is described as a variation example.

[0089] Figure 6 It is a block diagram showing a base station involved in the present invention.

[0090] like Figure 6As shown, the base station 60 includes a processor 601 and a memory 602. The processor 601 may include, for example, a microprocessor, a microcontroller, an embedded processor, etc. The memory 602 may include, for example, a volatile memory (such as a random access memory RAM), a hard disk drive (HDD), a non-volatile memory (such as a flash memory), or other memories, etc. The memory 602 stores program instructions. When the instructions are executed by the processor 601, the above method performed by the base station described in detail in the present invention may be executed.

[0091] Specifically, the base station according to the present invention communicates with the user equipment UE. When the multicast MCCH information changes, the base station notifies the UE that the multicast MCCH information has changed. Then, the base station sends the changed multicast MCCH information to the UE, and the multicast MCCH information is used to enable the UE to obtain or update the MRB or PTM configuration of the MBS multicast session established for receiving the MBS multicast session in the RRC inactive state, or to enable the UE to obtain or update the PTM configuration of the MBS multicast session indicated as being in the inactive state received in the RRC inactive state. For details, please refer to the above description.

[0092] In the embodiments of the present disclosure, when multiple operations are included, the embodiments of the present disclosure exemplarily list the execution order of each operation, and the embodiments obtained by changing the execution order of each operation are also within the protection scope of the present disclosure. In addition, when multiple judgment conditions are included, the embodiments obtained by changing the execution order of the judgment conditions are also within the protection scope of the present disclosure. In addition, in the present disclosure, unless otherwise specified, the meaning of a field defined in one embodiment may also be applied to the corresponding fields involved in other embodiments.

[0093] In addition, the computer executable instructions or programs running on the device according to the present invention can be programs that enable the computer to implement the functions of the embodiments of the present invention by controlling the central processing unit (CPU). The program or the information processed by the program can be temporarily stored in a volatile memory (such as a random access memory RAM), a hard disk drive (HDD), a non-volatile memory (such as a flash memory), or other memory systems.

[0094] The computer executable instructions or programs for realizing the functions of various embodiments of the present invention can be recorded on a computer readable storage medium. The corresponding functions can be realized by making a computer system read the programs recorded on the recording medium and executing these programs. The so-called "computer system" herein can be a computer system embedded in the device, and can include an operating system or hardware (such as a peripheral device). "Computer readable storage medium" can be a semiconductor recording medium, an optical recording medium, a magnetic recording medium, a recording medium of a short-term dynamic storage program, or any other recording medium readable by a computer.

[0095] The various features or functional modules of the devices used in the above embodiments can be implemented or executed by circuits (e.g., single-chip or multi-chip integrated circuits). Circuits designed to perform the functions described in this specification may include general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic, discrete hardware components, or any combination of the above devices. The general-purpose processor may be a microprocessor, or any existing processor, controller, microcontroller, or state machine. The above circuits may be digital circuits or analog circuits. In the case where new integrated circuit technologies have emerged to replace existing integrated circuits due to advances in semiconductor technology, one or more embodiments of the present invention may also be implemented using these new integrated circuit technologies.

[0096] In addition, the present invention is not limited to the above-mentioned embodiments. Although various examples of the embodiments have been described, the present invention is not limited thereto. Fixed or non-mobile electronic devices installed indoors or outdoors can be used as terminal devices or communication devices, such as AV equipment, kitchen equipment, cleaning equipment, air conditioners, office equipment, vending machines, and other household appliances.

[0097] As mentioned above, the embodiments of the present invention have been described in detail with reference to the accompanying drawings. However, the specific structure is not limited to the above embodiments, and the present invention also includes any design changes that do not deviate from the main purpose of the present invention. In addition, the present invention can be modified in various ways within the scope of the claims, and the embodiments obtained by appropriately combining the technical means invented by different embodiments are also included in the technical scope of the present invention. In addition, the components with the same effect described in the above embodiments can be replaced by each other.

Claims

1. A method performed by a user equipment UE, comprising: For a UE that is in an RRC inactive state and has joined one or more MBS multicast services, determining whether there is an MRB established for the purpose of receiving an MBS multicast session in the RRC inactive state; as well as If there is an MRB established for the purpose of receiving an MBS multicast session in an RRC inactive state, a multicast MCCH is detected or received.

2. The method according to claim 1, further comprising: If the MRB does not exist or is not established, the multicast MCCH is not detected or received.

3. A method performed by a user equipment UE, comprising: Receiving an RRC release message from a base station; as well as In a case where the received RRC release message includes information indicating the configuration in the RRC inactive state and the PTM configuration of the MBS multicast session received in the RRC inactive state, performing at least one of the following operations: If the MBS multicast session corresponding to the PTM configuration is indicated as being in an activated state, the PTM configuration is applied and MBS multicast reception in an RRC inactive state is performed; if the MBS multicast session corresponding to the PTM configuration is indicated as being in an inactive state, the PTM configuration is applied but MBS multicast reception in an RRC inactive state is not performed; If the MBS multicast session corresponding to the PTM configuration is indicated as being in an activated state, the PTM configuration is applied and the MBS multicast reception in the RRC inactive state is performed; if the MBS multicast session corresponding to the PTM configuration is indicated as being in an inactive state, a corresponding MRB is established according to the PTM configuration but the MBS multicast reception in the RRC inactive state is not performed; If the MBS multicast session corresponding to the PTM configuration is indicated as being in an activated state, applying the PTM configuration and performing MBS multicast reception in an RRC inactive state; if the MBS multicast session corresponding to the PTM configuration is indicated as being in an inactive state, saving the PTM configuration; If the MBS multicast session corresponding to the PTM configuration is indicated as being in an inactive state, applying the PTM configuration or saving the PTM configuration, and / or detecting or receiving a multicast MCCH; and Detect or receive multicast MCCH.

4. A method performed by a user equipment UE, comprising: For a UE that is in an RRC inactive state and has joined one or more MBS multicast services, determine whether there is an MRB established for the purpose of receiving an MBS multicast session in the RRC inactive state, or whether one or more joined MBS multicast sessions are indicated as being in an active state, or whether a PTM configuration of an MBS multicast session indicated as being in an inactive state is saved, or whether all saved PTM configurations of MBS multicast sessions received in the RRC INACTIVE state are indicated as being in an inactive state, or whether there is an MRB established for the purpose of receiving an MBS multicast session in the RRC INACTIVE state and the MBS multicast sessions are all in an inactive state; as well as If there is an MRB established for the purpose of receiving MBS multicast sessions in the RRC inactive state, or one or more joined MBS multicast sessions are indicated as being in the active state, or a PTM configuration of an MBS multicast session indicated as being in the inactive state is saved, or the saved PTM configurations of the MBS multicast sessions received in the RRC INACTIVE state are all indicated as being in the inactive state, or there is an MRB established for the purpose of receiving MBS multicast sessions in the RRC INACTIVE state and the MBS multicast sessions are all in the inactive state, then detect or receive the multicast MCCH.

5. The method according to claim 4, further comprising: If there is no PTM configuration for the MBS multicast session that has been joined and indicated as being in an active state and the MBS multicast session that has been joined and indicated as being in an inactive state, the multicast MCCH is not detected or received.

6. A method performed by a user equipment UE, comprising: For a UE that is in an RRC inactive state and has joined one or more MBS multicast services, determine whether it is configured as a special UE or a UE that assumes a leader role in a group, or is configured to detect MCCH, or is configured to be able to receive an MBS multicast session in an RRC inactive state, or is configured not to need to detect MCCH, or is configured not to be able to receive an MBS multicast session in an RRC inactive state; as well as If it is not configured as a special UE or is not configured as a UE that assumes a leader role in a group, or is configured to detect MCCH, or is configured to be able to receive MBS multicast sessions in an RRC inactive state, or is not configured not to need to detect MCCH, or is not configured to be unable to receive MBS multicast sessions in an RRC inactive state, then detect or receive the multicast MCCH.

7. The method according to claim 4 or 6, further comprising: In case that the PTM configuration of the MBS multicast session indicated by the TMGI is acquired through the multicast MCCH, applying the PTM configuration and performing MBS multicast reception in the RRC inactive state; and In case that the PTM configuration of the MBS multicast session indicated by the TMGI is not obtained through the multicast MCCH, but the UE locally stores the PTM configuration of the MBS multicast session indicated by the TMGI, the PTM configuration is applied and the MBS multicast reception in the RRC inactive state is performed.

8. A user equipment, comprising: processor; as well as Memory, which stores instructions, Wherein, when the instructions are executed by the processor, the method according to any one of claims 1 to 7 is performed.

9. A method performed by a base station, the base station communicating with a user equipment UE, the method comprising: When the multicast MCCH information changes, notifying the UE of the change in the multicast MCCH information; as well as sending the changed multicast MCCH information to the UE, The multicast MCCH information is used to enable the UE to obtain or update the MRB established for receiving an MBS multicast session in an RRC inactive state or the PTM configuration of the MBS multicast session, or to enable the UE to obtain or update the PTM configuration of an MBS multicast session indicated as being in an inactive state and received in an RRC inactive state.

10. A base station, comprising: processor; as well as Memory, which stores instructions, Wherein, the instructions, when executed by the processor, perform the method according to claim 9.

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