Method performed by user equipment, and user equipment

Abstract

The present invention provides a method performed by a user equipment, and a user equipment. The method performed by a user equipment (UE) comprises: when a UE is in a radio resource control (RRC) connected state, if the UE prioritizes reception of all multicast / broadcast service (MBS) frequencies of interest indicated to a network above reception of any unicast bearer and multicast MRB, sending a first indication identifier to the network; and if the UE prioritizes reception of all MBS frequencies of interest indicated to the network above reception of any multicast MRB, sending a second indication identifier to the network.

Description

Method performed by user equipment and user equipment Technical Field

[0001] The present invention relates to the technical field of wireless communications, and more particularly, to a method executed by a user equipment and the user equipment. Background Art

[0002] A study project (SI) on improving the 5G multicast broadcast service architecture (see SP-190625) has been approved. One of the objectives of this SI (referred to as Objective A) is to support universal MBS services in the 5GS. Use cases that could benefit from this feature include (but are not limited to) public safety, vehicle-to-everything (V2X) applications, transparent IPv4 / IPv6 multicast transmission, IPTV, wireless software delivery, group communications, and IoT applications. Accordingly, at the 3rd Generation Partnership Project (3GPP) RAN#86 plenary meeting, a work item on NR multicast and broadcast services (NRMBS) was proposed and approved (see non-patent document RP-193248: New WID: NR Multicast and Broadcast Service). This work item aims to provide support for Objective A in the RAN. The objectives of this work item have been largely achieved, and the relevant solutions are described in 3GPP Release 17 technical documents such as TS 38.300-h30, TS 38.331-h30, and TS 38.321-h30. At the 3GPP RAN#94 plenary meeting, a work item titled Enhanced NR Multicast and Broadcast Services was approved (see non-patent literature: RP-213568: New WID: Enhancements of NR Multicast and Broadcast Services). This work item aims to further enhance MBS Multicast and Broadcast Services in Release 17, with one of its goals being to support user equipment receiving MBS multicast services / sessions even when RRC is not active.

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

[0004] Summary of the Invention

[0005] In order to solve at least part of the above problems, the present invention provides a method performed by a user equipment and the user equipment.

[0006] According to a first aspect of the present invention, a method performed by a user equipment (UE) is provided, comprising: when the UE is in a radio resource control (RRC) connected state, if the UE prioritizes the reception of all multicast / broadcast service (MBS) frequencies of interest to the network over the reception of any unicast bearer and multicast MRB, sending a first indication identifier to the network; if the UE prioritizes the reception of all MBS frequencies of interest to the network over the reception of any multicast MRB, sending a second indication identifier to the network.

[0007] In the method of the first aspect above, preferably, the first indication identifier indicates whether the UE prioritizes the reception of all MBS frequencies of interest indicated to the network over the reception of any unicast bearer and multicast MRB; the second indication identifier indicates whether the UE prioritizes the reception of all MBS frequencies of interest indicated to the network over the reception of any multicast MRB.

[0008] In the method of the first aspect above, preferably, the UE in the RRC connected state initiates the MBS interest indication process when at least one of the following events occurs, the event comprising:

[0009] Event a1: Successfully establish or restore an RRC connection;

[0010] Event a2: entering or leaving a broadcast service area;

[0011] Event a3: MBS broadcast session starts or stops;

[0012] Event a4: Change of interest;

[0013] Event a5: The priority of MBS broadcast reception and unicast or MBS multicast reception changes;

[0014] Event a6: The priority of MBS broadcast reception and MBS multicast reception changes;

[0015] Event a7: Change to a primary cell (PCell) providing SIB21;

[0016] Event a8: SIB20 of a secondary cell (SCell) is received through dedicated signaling;

[0017] Event a9: switch;

[0018] Event a10: RRC connection re-establishment.

[0019] In the method of the first aspect above, preferably, when the UE initiates the MBS interest indication procedure, if the PCell provides SIB21, at least one of the following operations is performed:

[0020] Operation 1-1: Ensure that there is a valid version of SIB21 for the PCell;

[0021] Operation 1-2: If no MBS interest indication has been transmitted since the last entry into the RRC connected state, or if the UE connected to the PCell has not provided SIB21 since the UE last sent an MBS interest indication, then perform operation 1-2a, otherwise, perform operation 1-2b.

[0022] in,

[0023] Operation 1-2a: If the determined MBS broadcast frequency set of interest to the UE is not empty, set the content of the MBS interest indication and start transmitting the MBS interest indication message;

[0024] Action 1-2b: If the determined set of MBS broadcast frequencies of interest to the UE is different from the mbs-FreqList included in the last transmitted MBS Interest Indication, or if the reception priority of all indicated MBS broadcast frequencies compared to the reception of any established unicast bearers and multicast MRBs has changed since the last transmission of the MBS Interest Indication, or if the reception priority of all indicated MBS broadcast frequencies compared to the reception of any established multicast MRBs has changed since the last transmission of the MBS Interest Indication, then set the content of the MBS Interest Indication and initiate transmission of the MBS Interest Indication message.

[0025] In the method of the first aspect above, preferably, when a frequency satisfies at least one of the following conditions 1 to 3, the UE regards the frequency as part of the MBS frequency of interest:

[0026] Condition 1: At least one MBS session that the UE is receiving or interested in receiving via a broadcast MRB is in progress or about to start;

[0027] Condition 2: For at least one of these MBS sessions, the SIB21 obtained from the PCell includes a mapping between the relevant frequencies and one or more MBS FSAIs indicated in the USD for that session, or for at least one of these MBS sessions, the frequencies are not included in the SIB21 but are indicated in the USD for that session;

[0028] Condition 3: The UESupportedBandCombinationList contained in the E-NR-Capability contains at least one frequency band combination including the MBS frequency.

[0029] The one frequency is an MBS broadcast frequency or a frequency for transmitting an MBS broadcast or an MBS broadcast session.

[0030] In the method of the first aspect above, preferably, when at least one of the following conditions a to c is satisfied, the UE regards the MBS service as part of the MBS service of interest:

[0031] Condition a: The UE is receiving the service via the broadcast MRB or is interested in receiving the service;

[0032] Condition b: The service session is in progress or about to start;

[0033] Condition c: One or more MBS FSAIs in the USD of the service are contained in the SIB21 obtained from the PCell for a frequency belonging to the MBS frequency set of interest determined according to the procedure for determining the MBS broadcast frequency set of interest, or the SIB21 obtained from the PCell does not provide a frequency mapping for the relevant service, but the frequency is contained in the USD of the service.

[0034] In the method of the first aspect above, preferably, when the UE receives an indication to activate an MBS multicast session, or while an MBS multicast session is in progress, if the reception of the MBS multicast session conflicts with the reception of an MBS broadcast session with a higher priority, the UE initiates an RRC connection recovery process.

[0035] In the method of the first aspect above, preferably, when a UE in an RRC-inactive state receives an indication from the network to activate an MBS multicast session, and if the MBS multicast session is configured to allow reception in the RRC-inactive state and / or the UE has or obtains the PTM configuration of the MBS multicast session, if the reception of the MBS multicast session does not conflict with the reception of an MBS broadcast service that the UE is currently receiving or is interested in, the UE starts to receive the MBS multicast session in the RRC-inactive state.

[0036] In the method of the first aspect above, preferably, the UE starting to receive the MBS multicast session in the RRC inactive state is any one of the following operations:

[0037] Operation 1: The UE instructs the lower layer to detect the G-RNTI or G-CS-RNTI associated with the MBS multicast session;

[0038] Operation 2: The UE indicates to the lower layer that the MBS multicast session is activated and / or the G-RNTI or G-CS-RNTI associated with the MBS multicast session;

[0039] Operation 3: The UE indicates the MBS multicast session to the lower layer;

[0040] Operation 4: The UE instructs the lower layer to start / continue / resume receiving the MBS multicast session;

[0041] Operation 5: The UE remains in the RRC inactive state and starts detecting the G-RNTI or G-CS-RNTI corresponding to the TMGI;

[0042] Operation 6: If the MRB of the MBS multicast session has not been established, establish a corresponding MBR according to the received configuration information of the MBS multicast session.

[0043] In addition, according to a second aspect of the present invention, a user equipment is provided, comprising: a processor; and a memory storing instructions, wherein the instructions execute the method described above when executed by the processor.

[0044] Effects of the Invention

[0045] According to the method performed by the user equipment and the user equipment of the present invention, it is possible to effectively solve the relevant problems involved in the user equipment receiving MBS multicast services / sessions in the RRC inactive state, for example, it is possible to effectively solve the conflict that occurs when the user equipment receives MBS multicast sessions and MBS broadcast sessions in the RRC inactive state. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] 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:

[0047] FIG1 is a flowchart schematically showing a method executed by a user equipment UE according to embodiment 1 of the present invention.

[0048] FIG2 is a block diagram schematically showing a general structure of a user equipment according to the present invention. DETAILED DESCRIPTION

[0049] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that the present invention is not 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.

[0050] The following describes some of the terms involved in the present invention. For their specific meanings, please refer to the latest relevant 3GPP documents, such as TS38.300-h50, TS38.321-h50, TS38.323-h50, and TS38.331-h50. Furthermore, the embodiments of the present invention are described using broadcast / multicast services as an example. However, the embodiments of the present invention are not limited to broadcast / multicast services and can also be applied to other application scenarios.

[0051] UE: User Equipment.

[0052] RRC: Radio Resource Control.

[0053] RRC_CONNECTED: RRC connected state.

[0054] RRC_INACTIVE: RRC inactive state.

[0055] RRC_IDLE: RRC idle state.

[0056] RAN: Radio Access Network.

[0057] NR; New RAT, new radio access technology.

[0058] MBS: Multicast / Broadcast Services. Multicast can also be called multicast.

[0059] AS: Access Stratum, access layer or access layer.

[0060] NAS: Non Access Stratum, non-access layer or non-access layer.

[0061] RB: Radio Bearer. DRB is a data radio bearer.

[0062] MBS Radio Bearer (MRB): A radio bearer configured for MBS delivery. MRBs are classified into multicast MRBs and broadcast MRBs. A multicast MRB is a radio bearer configured for MBS multicast transmission, while a broadcast MRB is a radio bearer configured for MBS broadcast transmission.

[0063] TMGI: Temporary Mobile Group Identity, used to identify an MBS session.

[0064] RNTI: Radio Network Temporary Identifier, wireless network temporary identifier.

[0065] PTM (Point to Multipoint) is a method for delivering MBS services. In PTM, the gNB delivers a single copy of MBS data packets to a group of UEs. UEs use a G-RNTI or G-CS-RNTI to receive PTM transmissions. For example, the gNB uses the G-RNTI-based group-common physical downlink control channel (PDCCH) to schedule the same G-RNTI-based group-common physical downlink shared channel (PDSCH).

[0066] PTP: Point to Point, a delivery method for MBS services. In PTP, the gNB individually delivers separate copies of MBS data packets to each UE independently. For example, the base station schedules a UE-specific PDCCH scrambled with a UE-specific RNTI, using the same UE-specific RNTI, using the UE-specific PDSCH.

[0067] PCell: Primary Cell, MCG cell, operates on the primary frequency, in which the UE performs the initial connection establishment process or initiates the connection re-establishment process.

[0068] SCell: Secondary Cell. For UEs configured with carrier aggregation, an SCell is a cell that provides additional radio resources on top of a special cell. For dual connectivity, the term special cell refers to the PCell of an MCG or the PSCell of an SCG; otherwise, the term special cell refers to the PCell. For dual connectivity, the PSCell is the SCG cell in the secondary cell group (SCG) where the UE performs random access during the synchronous reconfiguration procedure.

[0069] G-RNTI: Group RNTI, group RNTI, used to scramble the scheduling and transmission of PTM for one or more MBS multicast services.

[0070] 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.

[0071] MTCH: MBS Traffic Channel, MBS traffic channel, is a PTM downlink channel used to transmit MBS data of a multicast session or broadcast session from the network to the UE. Unless otherwise specified, the MTCH involved in the embodiments of the present disclosure refers to the multicast MTCH used to transmit MBS multicast sessions.

[0072] MCCH: MBS Control Channel, MBS control channel, is a PTM downlink channel used for transmitting MBS broadcast or MBS multicast control information associated to one or several MTCH(s) from the network to the UE. MCCH includes broadcast MCCH and multicast MCCH.

[0073] The RRC recovery request message RRCResumeRequest or RRCResumeRequest1 is used to request the resumption of a suspended RRC connection or to perform a RAN-based notification area RNA update. When the UE initiates an RRC connection resumption request (i.e., RRC recovery request), if the 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 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 resume a suspended RRC connection. In the present disclosure, the useFullResumeID field indicates the resume identifier and resume request message to be used. When the field is included in SIB1, the fullI-RNTI and RRCResumeRequest1 message are used. When the field is not included in SIB1, the shortI-RNTI and RRCResumeRequest message are used. The shortI-RNTI uses fewer bits than the I-RNTI-Value to identify the suspended UE context of a UE in the RRC Inactive state.

[0074] In the present invention, network, base station and RAN can be used interchangeably. 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.

[0075] Currently, NR MBS services include MBS broadcast (also known as MBS broadcast session, broadcast MBS, MBS broadcast service, or MBS broadcast service) and MBS multicast (also known as MBS multicast session, multicast MBS, MBS multicast service, or MBS multicast service). MBS broadcast provides a downlink-only MBS transmission mode for services with low quality of service (QoS), allowing UEs in RRC connected, RRC idle, and RRC inactive states to receive the MBS service. UEs obtain MBS broadcast configuration information broadcast by the network through the MBS control channel (MCCH). In 3GPP version 17, before receiving MBS multicast services (i.e., MBS multicast sessions), a UE needs to establish an RRC connection with the base station. The base station then configures resources for the UE to receive MBS multicast services through dedicated RRC signaling (also known as RRC messages, such as RRC reconfiguration messages). 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 that are in an RRC connected state and have MRBs configured can receive the corresponding MBS multicast services.

[0076] In version 17, it is not supported for UEs 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 that supports MBS multicast notifies the UEs in RRC idle state or RRC inactive state through a group notification mechanism. Upon receiving the group notification, the UEs that have joined or are interested in the MBS multicast session establish or resume an RRC connection with the network to receive the corresponding MBS multicast session. The group notification is addressed with P-RNTI on 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).

[0077] Version 18 supports UEs receiving MBS multicast sessions in an RRC inactive state. For MBS multicast sessions received in an RRC inactive state, the base station can provide or configure the UE with PTM configuration information for receiving the MBS multicast session (also called MBS multicast session configuration information or MBS multicast session PTM configuration) through dedicated RRC signaling (e.g., RRCRelease message) or through the multicast MBS control channel MCCH (i.e., multicast MCCH). The information required to obtain the multicast MCCH (or multicast MCCH configuration) can be configured for the 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 the MBS multicast received in the 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 MBS 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, in the embodiments of the present disclosure, the MBS multicast session being in an active state or being activated means that the MBS multicast session is in progress or about to start, or the UE starts receiving the MBS multicast session. The network can indicate to the UE that the MBS multicast is activated through RRC signaling (e.g., an 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 receiving the MBS multicast session after receiving the indication. In the embodiment of 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 indicator identifier is associated with each MBS multicast session to explicitly indicate that the MBS multicast session is deactivated) or through the physical downlink control channel PDCCH (or downlink control information DCI) 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. The UE stopping receiving the MBS multicast session may be that the UE does not detect the G-RNTI or G-CS-RNTI corresponding to the MBS multicast session.

[0078] Each MBS multicast session is identified by a TMGI and 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 MAC entity's G-RNTI(s)and G-CS-RNTI(s).

[0079] A UE may be concurrently participating in one or more MBS multicast sessions and MBS broadcast sessions. If a UE is configured to receive MBS multicast sessions in the RRC_INACTIVE state, it may need to receive both one or more MBS multicast sessions and one or more MBS broadcast sessions simultaneously while in the RRC_INACTIVE state. However, due to limitations on the UE's capabilities, it is not capable of receiving both. Therefore, how can conflicts between receiving an MBS multicast session and an MBS broadcast session in the RRC_INACTIVE state be resolved?

[0080] To address at least some of the above problems, the present disclosure provides corresponding embodiments. Specific embodiments are listed below to illustrate the processing method of the present invention. Furthermore, the embodiments listed below are merely illustrative and do not limit the present invention.

[0081] Example 1

[0082] Hereinafter, the first embodiment of the present invention will be described with reference to the accompanying drawings. Fig. 1 is a flowchart schematically showing a method executed by a user equipment UE according to the first embodiment of the present invention.

[0083] As shown in Figure 1, when the UE is in the RRC connected state, if the UE prioritizes the reception of all MBS frequencies of interest to the network (i.e., the reception of MBS broadcasts or MBS broadcast sessions) over the reception of any unicast bearer (i.e., unicast) and multicast MRB (or the MBS multicast or MBS multicast session to which the UE has joined), a first indication identifier is sent to the network (step S101); if the UE prioritizes the reception of all MBS frequencies of interest to the network over the reception of any multicast MRB (or the MBS multicast or MBS multicast session to which the UE has joined), a second indication identifier is sent to the network (step S102). Among them, the first indication identifier indicates whether the UE prioritizes the reception of all MBS frequencies of interest to the network (i.e., the reception of MBS broadcasts or MBS broadcast sessions) over the reception of any unicast bearer (i.e., unicast) and multicast MRB (or the MBS multicast or MBS multicast session to which the UE has joined). If the UE prioritizes the reception of all MBS frequencies of interest to the network (i.e., the reception of MBS broadcasts or MBS broadcast sessions) over the reception of any unicast bearer (i.e., unicast) and multicast MRB (or the MBS multicast or MBS multicast session to which the UE has joined), the UE sends the first indication identifier to the network (its value can be set to "true"); otherwise, the UE does not send the first indication identifier to the network (optional). The second indication identifier indicates whether the UE prioritizes the reception of all MBS frequencies of interest indicated to the network (i.e., the reception of MBS broadcasts or MBS broadcast sessions) over the reception of any multicast MRB (or the MBS multicast or MBS multicast session to which the UE has joined). If the UE prioritizes the reception of all MBS frequencies of interest indicated to the network (i.e., the reception of MBS broadcasts or MBS broadcast sessions) over the reception of any multicast MRB (or the MBS multicast or MBS multicast session to which the UE has joined), the UE sends the second indication identifier to the network (its value can be set to "true"); otherwise, the UE does not send the second indication identifier to the network (optional), or sends the second indication identifier to the network but its value is set to "false" (optional). In addition, the MBS frequency and / or the first indication identifier and / or the second indication identifier indicated to the network by the UE in which it is interested can all be carried in the same RRC message, for example, carried in an MBS interest indication MBSInterestIndication message sent by the UE to the network, wherein the MBSInterestIndication message is used to notify the network that the UE is currently receiving or is interested in receiving, or is no longer receiving or is no longer interested in receiving, one or more MBS broadcast services via a broadcast MRB. It can be provided that only if the UE has the capability of receiving MBS multicast or an MBS multicast session in the RRC_INACTIVE state, will the second indication identifier be sent to the network if the above-mentioned conditions are met.

[0084] Specifically, when initiating the MBS Interest Indication procedure, the UE performs the following operations:

[0085] If the PCell provides SIB21, perform at least one of the following operations:

[0086] Operation 1-1: Ensure that there is a valid version of SIB21 for the PCell;

[0087] Operation 1-2: If no MBS interest indication (i.e., MBS interest indication message) has been transmitted since the last entry into the RRC connected state, or if the UE connected to the PCell has not provided SIB21 since the UE last sent an MBS interest indication, perform operation 1-2a, otherwise, perform operation 1-2b.

[0088] Operation 1-2a: If the determined MBS broadcast frequency set that the UE is interested in is not empty, set the content of the MBS interest indication and start transmitting the MBS interest indication message.

[0089] Action 1-2b: If the determined set of MBS broadcast frequencies of interest to the UE is different from the mbs-FreqList included in the last transmitted MBS Interest Indication, or if the reception priority of all indicated MBS broadcast frequencies has changed compared to reception of any established unicast bearers and multicast MRBs since the last transmission of the MBS Interest Indication, or if the reception priority of all indicated MBS broadcast frequencies has changed compared to reception of any established multicast MRBs (or MBS multicasts to which the UE has joined or MBS multicast sessions to which the UE has joined), then set the content of the MBS Interest Indication, and start transmitting an MBS interest indication message; otherwise, if SIB20 is provided in the PCell or SCell, further, if (1) since the last time the UE sent an MBS interest indication, the UE has been connected to a PCell that does not provide SIB20 and the UE has not been provided with SIB20 for the SCell, or (2) the set of MBS broadcast services of interest determined by the UE is different from the mbs-ServiceList included in the last transmission of the MBS interest indication, then set the content of the MBS interest indication and start transmitting the MBS interest indication message. Among them, the mbs-FreqList field is used to indicate the MBS frequency list of the MBS broadcast services that the UE is receiving or interested in receiving via broadcast MRBs, and the mbs-ServiceList field refers to the list of MBS broadcast services that the UE is receiving or interested in receiving.

[0090] Optionally, the above operations 1-1 and 1-2 are for a UE in an RRC connected state.

[0091] A UE in RRC_INACTIVE state that has the capability to receive MBS multicast (or MBS multicast session) in RRC_INACTIVE state or is configured to receive MBS multicast (or MBS multicast session) in RRC_INACTIVE state initiates the RRC recovery procedure if the determined set of MBS broadcast frequencies of interest to the UE is different from the mbs-FreqList included in the last transmitted MBS interest indication, or if the reception priority of all indicated MBS broadcast frequencies has changed since the last transmission of the MBS interest indication, compared to the reception of any established multicast MRB (or an MBS multicast session to which the UE has joined or an MBS multicast to which the UE has joined or any MBS multicast configured to be received in RRC_INACTIVE state).

[0092] In addition, when a UE with MBS capability and in an RRC connected state has at least one of the following events a1-a10, the MBS interest indication process is initiated.

[0093] Event a1: Successfully establish or restore an RRC connection;

[0094] Event a2: entering or leaving a broadcast service area;

[0095] Event a3: MBS broadcast session starts or stops;

[0096] Event a4: Change of interest;

[0097] Event a5: The priority of MBS broadcast reception and unicast or MBS multicast reception changes;

[0098] Event a6: The priority of MBS broadcast reception and MBS multicast reception changes;

[0099] Event a7: Change to a PCell (primary cell) providing SIB21;

[0100] Event a8: SIB20 of an SCell is received via dedicated signaling;

[0101] Event a9: switch;

[0102] Event a10: RRC connection re-establishment.

[0103] In the embodiment of the present disclosure, SIB21 contains the mapping between the current and / or adjacent carrier frequencies and the MBS Frequency Selection Area Identifier (FSAI). SIB20 contains the information required to obtain the MCCH configuration of the MBS broadcast.

[0104] The following describes an embodiment of setting the content of the MBS interest indication:

[0105] The UE sets the content of the MBS interest indication as follows:

[0106] If the MBS broadcast frequency set of interest determined by the UE is not empty, the UE performs at least one of the following operations:

[0107] Operation 3-1: Include the information element mbs-FreqList in the MBS interest indication (or MBS interest indication message) and include the MBS frequencies of interest in the mbs-FreqList in descending order of interest (from strong to weak interest). If applicable, the MBS frequencies of interest use absoluteFrequencySSB for serving frequency, and the ARFCN-ValueNR(s) as included in SIB21 or in USD (for neighboring frequencies). The absoluteFrequencySSB field is used for the SSB frequency of the serving cell. The ARFCN-ValueNR field is used to indicate the ARFCN applicable to the downlink, uplink, or bidirectional (TDD) NR global frequency grid.

[0108] Operation 3-2: If the UE prioritizes the reception of all indicated MBS frequencies (i.e., frequencies of MBS broadcasts) (indicated in the MBS interest indication or included in the mbs-FreqList) over the reception of any unicast bearer and multicast MRB (or MBS multicast or MBS multicast session that the UE has joined), then a first indication identifier is included in the MBS interest indication (or MBS interest indication message).

[0109] Operation 3-3: If the UE prioritizes the reception of all indicated MBS frequencies (indicated in the MBS interest indication or included in the mbs-FreqList) over the reception of any multicast MRB (or MBS multicast or MBS multicast session that the UE has joined), a second indication identifier is included in the MBS interest indication (or MBS interest indication message).

[0110] It should be noted that, in the embodiment of the present disclosure, the UE prioritizes the reception of all indicated MBS frequencies (indicated in the MBS interest indication or included in the mbs-FreqList) over the reception of any multicast MRB (or the MBS multicast or MBS multicast session to which the UE has joined) can be replaced by the UE prioritizing the reception of all indicated MBS frequencies (indicated in the MBS interest indication or included in the mbs-FreqList) over the reception of any multicast MRB configured for reception in the RRC_INACTIVE state (or the MBS multicast or MBS multicast session to which the UE has joined and configured for reception in the RRC_INACTIVE state).

[0111] The following describes an embodiment in which a UE determines an MBS broadcast frequency set of interest.

[0112] When a frequency (i.e., an MBS broadcast frequency or a frequency transmitting an MBS broadcast or MBS broadcast session) satisfies the following conditions 1 and / or 2 and / or 3, the UE regards the frequency as part of the MBS frequencies of interest:

[0113] Condition 1: At least one MBS session that the UE is receiving or interested in receiving via a broadcast MRB is in progress or about to start (the MBS session is transmitted on the frequency).

[0114] Condition 2: for at least one of these MBS sessions, SIB21 acquired from the PCell includes mapping between the concerned frequency and one or more MBS FSAIs indicated in the USD for this session, or for at least one of these MBS sessions, the concerned frequency is not included in SIB21 but is indicated in the USD for this session.

[0115] Condition 3: The supportedBandCombinationList the UE included in UE-NR-Capability contains at least one band combination including the concerned MBS frequency. E-NR-Capability is used to convey NR UE radio access capability parameters, and supportedBandCombinationList is a list of band combinations supported by the UE for NR (and NR-DC, if required).

[0116] The following describes an embodiment in which a UE determines an MBS broadcast service set of interest.

[0117] An MBS Service is considered to be part of the MBS Service of Interest if the following Condition a and / or Condition b and / or Condition c are met:

[0118] Condition a: The UE is receiving the service via the broadcast MRB or is interested in receiving the service;

[0119] Condition b: The service session is in progress or about to start;

[0120] Condition c: one or more MBS FSAIs in the USD for this service is included in SIB21 acquired from the PCell for a frequency belonging to the set of MBS frequencies of interest, determined according to MBS frequencies of interest determination procedure or SIB21 acquired from the PCell does not provide the frequency mapping for the concerned service but that frequency is included in the USD of this service.

[0121] Example 2

[0122] Upon receiving an indication to activate an MBS multicast session or resume MBS multicast session data transmission, if reception of the MBS multicast session conflicts with reception of a higher priority MBS broadcast session, an RRC connection recovery procedure is initiated. The MBS multicast session is an MBS multicast session that the UE has joined.

[0123] Specifically, when a UE in the RRC_INACTIVE state receives an indication from the network to activate an MBS multicast session or resume MBS multicast session data transmission (for example, the TMGI of the MBS multicast session is included in the received paging message), if the MBS multicast session is configured to be able to or allowed to be received in the RRC_INACTIVE state and / or the UE has or obtains the PTM configuration of the MBS multicast session, and / or if the reception of the MBS multicast session conflicts with the reception of a higher-priority MBS broadcast service that the UE is receiving or interested in (or is interested in and is about to start) (for example, the UE cannot receive both services at the same time), and / or the UE identifier contained in the paging message does not match or is the same as the UE identifier allocated by the upper layer, the UE initiates the RRC connection recovery process. Optionally, when the MBS multicast session is configured to be able to or allowed to be received in the RRC_INACTIVE state and / or the UE has or obtains the PTM configuration of the MBS multicast session, and / or if the reception of the MBS multicast session does not conflict with the reception of a higher priority MBS broadcast service that the UE is currently receiving or interested in (or is interested in and is about to start), and / or the UE identifier contained in the paging message does not match or is the same as the UE identifier allocated by the upper layer, the UE starts to receive the MBS multicast session in the RRC inactive state.

[0124] In the embodiments of the present disclosure, the activation of an MBS multicast session or the resumption of MBS multicast session data transmission may be achieved by including the TMGI of the MBS multicast session in a paging message. When the UE receives the paging message from the base station, it deems that the MBS multicast session indicated by the TMGI is activated or data transmission is resumed, or that reception of the MBS multicast session indicated by the TMGI is started. The MBS multicast session is configured to be received or allowed to be received in the RRC_INACTIVE state, which can be configured or indicated by an RRC release message and / or a paging message. In one implementation, if the paging message carries the inactiveReceptionAllowed field corresponding to the TMGI, the MBS multicast session indicated by the TMGI is considered to be configured to be received or allowed to be received in the RRC_INACTIVE state; in another implementation, if the MBS multicast session is configured to be received in the RRC_INACTIVE state in the RRC release message and the paging message contains the inactiveReceptionAllowed field corresponding to the MBS multicast session, the MBS multicast session is considered to be configured to be received or allowed to be received in the RRC_INACTIVE state. Among them, the field inactiveReceptionAllowed indicates whether the UE with a valid PTM configuration (i.e., the valid PTM configuration of the MBS multicast session indicated by the TMGI) remains in RRC_INACTIVE to receive the corresponding MBS multicast session for the TMGI included in the pagingGroupList (the UE has joined the MBS multicast session indicated by the TMGI), and the pagingGroupList is a field included in the paging message, and the pagingGroupList is used to include the inactiveReceptionAllowed field that corresponds one-to-one to the TMGI included in the paging message.

[0125] Example 3

[0126] During an ongoing MBS multicast session, if reception of the MBS multicast session conflicts with reception of a higher priority MBS broadcast session (i.e., a higher priority MBS broadcast service that the UE is currently receiving or interested in (or is interested in and is about to start)), the RRC connection recovery procedure is initiated.

[0127] Example 4

[0128] When a UE in the RRC_INACTIVE state receives an indication from the network to activate an MBS multicast session or to resume data transmission of an MBS multicast session, if the MBS multicast session is configured to be able to or allowed to be received in the RRC_INACTIVE state and / or the UE has or has obtained the PTM configuration for the MBS multicast session:

[0129] If the reception of the MBS multicast session does not conflict with the reception of an MBS broadcast service that the UE is currently receiving or interested in (or is interested in and is about to start) (for example, the UE cannot receive these two services at the same time), the UE starts receiving the MBS multicast session in the RRC inactive state.

[0130] Optionally, if the reception of the MBS multicast session conflicts with the reception of an MBS broadcast service that the UE is currently receiving or is interested in (or is interested in and is about to start) (for example, the UE cannot receive both services at the same time), the UE initiates an RRC connection recovery procedure.

[0131] Optionally, if the reception of the MBS multicast session conflicts with the reception of an MBS broadcast service that the UE is currently receiving or is interested in (or is interested in and is about to start) (for example, the UE cannot receive both services at the same time), the UE does not initiate the process of starting to receive the MBS multicast session in the RRC_INACTIVE state or the UE suspends the activated MBS multicast session.

[0132] Optionally, when the UE ends receiving the MBS broadcast session (or an MBS broadcast session with a higher priority), and / or if the MBS multicast session that previously conflicted with the MBS broadcast session has not been deactivated (or there is a suspended MBS multicast session in an active state, and the MBS multicast session is an MBS multicast session that conflicts with the reception and transmission of the MBS broadcast session), the UE starts receiving the MBS multicast session in the RRC_INACTIVE state.

[0133] Optionally, the MBS broadcast service that the UE is currently receiving or interested in (or is interested in and is about to start) in Example 4 refers to an MBS broadcast service that the UE is currently receiving or interested in (or is interested in and is about to start) and has a higher priority than the priority of the MBS multicast session.

[0134] In addition, in the embodiment of the present disclosure, starting to receive the MBS multicast session in the RRC inactive state may be one of the following operations:

[0135] Operation 1: The UE (ie, the RRC layer of the UE) instructs a lower layer (the lower layer may be a MAC layer) to monitor the G-RNTI or G-CS-RNTI associated with the MBS multicast session.

[0136] Operation 2: The UE (ie, the RRC layer of the UE) indicates to a lower layer (the lower layer may be a MAC layer) that the MBS multicast session is activated and / or the G-RNTI or G-CS-RNTI associated with the MBS multicast session.

[0137] Operation 3: Indicate the MBS multicast session to a lower layer (the lower layer may be a MAC layer).

[0138] Operation 4: Instruct a lower layer (the lower layer may be a MAC layer) to start / continue / resume receiving the MBS multicast session.

[0139] Operation 5: Maintain RRC_INACTIVE and start detecting the G-RNTI(s) or G-CS-RNTI(s) corresponding to the TMGI(s).

[0140] Operation 6: If the MRB for the MBS multicast session has not been established, establish a corresponding MBR based on the received configuration information for the MBS multicast session and / or perform one of Operations 1-5. Optionally, after establishing the MRB, forward the TMGI of the MBS multicast session to an upper layer. Optionally, if the MRB for the MBS multicast session has been established, continue or resume the MRB and / or perform one of Operations 1-5.

[0141] FIG2 is a block diagram illustrating a simplified structure of a user device 20 according to the present invention. As shown in FIG2 , the user device 20 includes a processor 201 and a memory 202. The processor 201 may include, for example, a microprocessor, a microcontroller, or an embedded processor. The memory 202 may include, for example, a volatile memory (e.g., a random access memory (RAM)), a hard disk drive (HDD), a non-volatile memory (e.g., a flash memory), or other memory. The memory 202 stores program instructions. When executed by the processor 201, these instructions may execute the aforementioned method performed by the user device, as described in detail in this disclosure.

[0142] In the embodiments of the present disclosure, when multiple operations are involved, 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 scope of protection of the present disclosure. In addition, when multiple judgment conditions are involved, the embodiments obtained by changing the execution order of each judgment condition are also within the scope of protection of the present disclosure. In addition, in the present disclosure, unless otherwise specified, the meaning of the fields defined in one embodiment may also be applied to the corresponding fields involved in other embodiments. In addition, in the embodiments of the present disclosure, "if...", "when...", "when...", "at...", "satisfy..." or "satisfy the conditions..." can be replaced with "under the condition of...".

[0143] 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.

[0144] The computer executable instructions or programs for realizing each embodiment of the present invention function can be recorded on a computer-readable storage medium. The corresponding functions can be realized by making a computer system read the program 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 short-term dynamic storage program recording medium or any other recording medium that is computer-readable.

[0145] 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). The circuits designed to perform the functions described in this specification may include 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 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 event that 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.

[0146] Furthermore, the present invention is not limited to the above-described 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.

[0147] As described 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-described embodiments, and the present invention also includes any design changes that do not deviate from the main purpose of the present invention. In addition, various modifications can be made to the present invention within the scope of the claims, and 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, components with the same effect described in the above embodiments can be replaced with each other.

Claims

1. A method performed by a user equipment UE, comprising: When the UE is in a radio resource control (RRC) connected state, If the UE indicates to the network that reception of all multicast / broadcast service MBS frequencies of interest takes precedence over reception of any unicast bearer and multicast MRB, sending a first indication identifier to the network; If the UE prioritizes the reception of all MBS frequencies of interest indicated to the network over the reception of any multicast MRB, a second indication identifier is sent to the network.

2. The method according to claim 1, wherein: The first indication flag indicates whether the UE prioritizes reception of all MBS frequencies of interest indicated to the network over reception of any unicast bearers and multicast MRBs; The second indication flag indicates whether the UE prioritizes reception of all MBS frequencies of interest indicated to the network over reception of any multicast MRBs.

3. The method performed by a user equipment UE according to claim 1 or 2, wherein: The UE in the RRC connected state starts the MBS interest indication process when at least one of the following events occurs, wherein: Event a1: Successfully establish or restore the RRC connection; Event a2: entering or leaving a broadcast service area; Event a3: MBS broadcast session starts or stops; Event a4: Change of interest; Event a5: The priority of MBS broadcast reception and unicast or MBS multicast reception changes; Event a6: The priority of MBS broadcast reception and MBS multicast reception changes; Event a7: Change to a primary cell PCell providing SIB21; Event a8: receiving SIB20 of a secondary cell SCell through dedicated signaling; Event a9: switch; Event a10: RRC connection reestablishment.

4. The method performed by a user equipment UE according to claim 1 or 2, wherein: When the UE initiates the MBS interest indication procedure, if the PCell provides SIB21, at least one of the following operations is performed: Operation 1-1: Ensure that there is a valid version of SIB21 of the PCell; Operation 1-2: If no MBS interest indication has been transmitted since the last entry into the RRC connected state, or if the UE connected to the PCell has not provided SIB21 since the UE last sent an MBS interest indication, then perform operation 1-2a, otherwise, perform operation 1-2b, in, Operation 1-2a: If the determined MBS broadcast frequency set of interest to the UE is not empty, setting the content of the MBS interest indication, and starting to transmit the MBS interest indication message; Action 1-2b: If the determined set of MBS broadcast frequencies of interest to the UE is different from the mbs-FreqList included in the last transmitted MBS Interest Indication, or if the reception priority of all indicated MBS broadcast frequencies has changed compared to reception of any established unicast bearers and multicast MRBs since the last transmission of the MBS Interest Indication, or if the reception priority of all indicated MBS broadcast frequencies has changed compared to reception of any established multicast MRBs since the last transmission of the MBS Interest Indication, then set the content of the MBS Interest Indication and initiate transmission of the MBS Interest Indication message.

5. The method performed by a user equipment UE according to claim 1 or 2, wherein: When a frequency satisfies at least one of the following conditions 1 to 3, the UE regards the frequency as part of the MBS frequency of interest: Condition 1: At least one MBS session that the UE is receiving or interested in receiving via the broadcast MRB is in progress or about to start; Condition 2: For at least one of these MBS sessions, the SIB21 obtained from the PCell includes a mapping between the relevant frequencies and one or more MBS FSAIs indicated in the USD for this session, or for at least one of these MBS sessions, the frequencies are not included in the SIB21 but are indicated in the USD for this session; Condition 3: The UEsupportedBandCombinationList contained in the E-NR-Capability contains at least one frequency band combination including the MBS frequency, The one frequency is an MBS broadcast frequency or a frequency for transmitting an MBS broadcast or an MBS broadcast session.

6. The method performed by a user equipment UE according to claim 1 or 2, wherein: When at least one of the following conditions a to c is met, the UE regards the MBS service as a part of the MBS service of interest: Condition a: The UE is receiving the service via broadcast MRB or is interested in receiving the service; Condition b: The session of the service is in progress or about to start; Condition c: One or more MBS FSAIs in the USD of the service are contained in SIB21 obtained from the PCell for a frequency belonging to the MBS frequency set of interest determined according to the procedure for determining the MBS broadcast frequency set of interest, or the SIB21 obtained from the PCell does not provide frequency mapping for the relevant service, but the frequency is included in the USD of the service.

7. The method performed by a user equipment UE according to claim 1 or 2, wherein: When the UE receives an indication to activate an MBS multicast session, or when the MBS multicast session is in progress, if reception of the MBS multicast session conflicts with reception of an MBS broadcast session with a higher priority, the UE initiates an RRC connection recovery procedure.

8. The method performed by a user equipment UE according to claim 1 or 2, wherein: When a UE in an RRC inactive state receives an indication from the network to activate an MBS multicast session, if the MBS multicast session is configured to allow reception in an RRC inactive state and / or the UE has or obtains a PTM configuration for the MBS multicast session, If the reception of the MBS multicast session does not conflict with the reception of an MBS broadcast service that the UE is currently receiving or is interested in, the UE starts receiving the MBS multicast session in an RRC inactive state.

9. The method performed by the user equipment UE according to claim 8, wherein: The UE starting to receive the MBS multicast session in the RRC inactive state is any one of the following operations: Operation 1: The UE instructs the lower layer to detect the G-RNTI or G-CS-RNTI associated with the MBS multicast session; Operation 2: The UE indicates to the lower layer that the MBS multicast session is activated and / or the G-RNTI or G-CS-RNTI associated with the MBS multicast session; Operation 3: The UE indicates the MBS multicast session to the lower layer; Operation 4: The UE instructs the lower layer to start / continue / resume receiving the MBS multicast session; Operation 5: The UE remains in the RRC inactive state and starts detecting the G-RNTI or G-CS-RNTI corresponding to the TMGI; Operation 6: If the MRB of the MBS multicast session has not been established, establish a corresponding MBR according to the received configuration information of the MBS multicast session.

10. A user equipment, comprising: processor; as well as A memory storing instructions; When the instructions are executed by the processor, the user equipment is caused to perform the method according to any one of claims 1 to 9.

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