Multicast broadcast traffic in various radio resource control states

Abstract

The disclosed aspects relate to managing multicast broadcast services (MBS) in different radio resource control (RRC) states, including a wireless communication device receiving a point-to-multipoint (PTM) configuration of each of a plurality of MBSs from a network using wireless communication device-specific signaling, when the wireless communication device is in an RRC connected state. The wireless communication device transitions from an RRC connected state to an RRC inactive state. In response to transitioning to the RRC inactive state, when the wireless communication device is in the RRC inactive state, the wireless communication device receives data of at least one of the plurality of MBSs from the network using the PTM configuration received in the RRC connected state.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application is related to an application filed on May 31, 2022, with agency docket number ZTE-2022-000613-WO, entitled “Multicast Broadcast Service in Different Radio Resource Controls”, the disclosure of which is incorporated herein by reference in its entirety. This application is also related to an application filed on May 31, 2022, with agency docket number ZTE-2022-000896-WO, entitled “Multicast Broadcast Service in Different Radio Resource Controls”, the disclosure of which is incorporated herein by reference in its entirety. Technical Field

[0003] The present invention relates to wireless communications, and more particularly, to a system, method, device and non-volatile computer-readable medium for managing a multicast and broadcast service (MBS) under various radio resource control (RRC) states. Background Art

[0004] MBS is one of the most prominent use cases of the Fifth Generation (5G) New Radio (NR), providing reliable, low-latency, and resource-efficient transmission to multiple terminals receiving the same content. The main use scenarios of MBS include deployment in crowded areas with a high concentration of terminals, such as concerts, stadiums, racetracks, rallies, densely populated areas, etc., to send the same content (e.g., the same video). In some embodiments, MBS content (e.g., video) is synchronized to the terminals, and multiple perspectives of the video are required. In addition, a large number of users and terminals in the same cell watch virtual reality (VR) live broadcasts at the same time. Summary of the invention

[0005] In some examples, when the wireless communication device is in an RRC connected state, the wireless communication device receives a point-to-multipoint (PTM) configuration for each of a plurality of MBSs from a network using signaling specific to the wireless communication device. The wireless communication device transitions from the RRC connected state to an RRC inactive state. In response to transitioning to the RRC inactive state, when the wireless communication device is in the RRC inactive state, the wireless communication device receives data for at least one of the plurality of MBSs from the network using the PTM configuration received in the RRC connected state.

[0006] In some examples, when the wireless communication device is in an RRC connected state, the network sends a PTM configuration for each of the multiple MBSs to the wireless communication device using signaling specific to the wireless communication device. The network releases the wireless communication device to an RRC inactive state. When the wireless communication device is in an RRC inactive state, the network sends data corresponding to at least one of the multiple MBSs to the wireless communication device using the PTM configuration sent when the UE was in an RRC connected state.

[0007] In some examples, when the wireless communication device is in an RRC connected state, the wireless communication device receives indication information from the network, the indication information indicating that a PTM configuration for each of the multiple MBSs is obtained from broadcast signaling. The wireless communication device receives from the network a PTM configuration for receiving broadcast signaling of multiple MBSs when the wireless communication device is in an RRC connected state.

[0008] In some examples, the network sends indication information to the wireless communication device using signaling specific to the wireless communication device, the indication information indicating that when the wireless communication device is in an RRC connected state, a PTM configuration for each of the multiple MBSs is obtained from broadcast signaling for sending the multiple MBSs, and when the wireless communication device is in an RRC inactive state, a PTM configuration for each of the multiple MBSs is obtained from at least one MBS. The network sends the wireless communication device a PTM configuration for sending the multiple MBSs when the wireless communication device is in an RRC connected state and an updated PTM configuration for sending at least one MBS when the wireless communication device is in an RRC inactive state using broadcast signaling.

[0009] In some examples, the wireless communication device receives from the network a PTM configuration for receiving at least one MBS when the wireless communication device is in an RRC connected state using first signaling specific to the wireless communication device. When the wireless communication device is in the RRC connected state, the wireless communication device receives indication information from the network using second signaling specific to the wireless communication device, the indication information indicating that when the wireless communication device is in an RRC inactive state, the PTM configuration for receiving at least one MBS is obtained from broadcast signaling.

[0010] In some examples, the network sends a PTM configuration for receiving at least one MBS when the wireless communication device is in an RRC connected state to the wireless communication device using a first signaling specific to the wireless communication device. When the wireless communication device is in the RRC connected state, the network sends indication information to the wireless communication device using a second signaling specific to the wireless communication device, the indication information indicating that when the wireless communication device is in an RRC inactive state, the PTM configuration for receiving the at least one MBS is obtained from broadcast signaling.

[0011] The above and other aspects and implementations thereof are described in more detail in the drawings, description and claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] These and other aspects and features of the present implementations will be apparent to one of ordinary skill in the art upon reading the following description of specific implementations in conjunction with the accompanying drawings, in which:

[0013] Figure 1 is a schematic diagram illustrating an exemplary wireless communication network according to various aspects.

[0014] Figure 2 is a schematic diagram illustrating a block diagram of an example wireless communication system for transmitting and receiving downlink and uplink communication signals in accordance with various aspects.

[0015] Figure 3 A flow chart of an exemplary method for managing an MBS according to various aspects is shown.

[0016] Figure 4 A flow chart of an exemplary method for managing an MBS according to various aspects is shown.

[0017] Figure 5 is a flow chart illustrating an exemplary method for managing an MBS according to various aspects.

[0018] Figure 6 is a table illustrating an embodiment PTM configuration carried in a dedicated RRC reconfiguration dedicated to a UE according to different schemes.

[0019] Figure 7 is a table illustrating embodiment broadcast PTM configurations carried in MCCH according to some aspects.

[0020] Figure 8 is a flow chart illustrating an exemplary method for managing an MBS according to various aspects.

[0021] Fig. 9 is a flow chart illustrating an exemplary method for managing an MBS according to various aspects.

[0022] Fig.10 is a flow chart illustrating an exemplary method for managing an MBS according to various aspects.

[0023] Fig.11 is a flow chart illustrating an exemplary method for managing an MBS according to various aspects.

[0024] Fig.12 is a flow chart illustrating an exemplary method for managing an MBS according to various aspects.

[0025] Fig.13 is a flow chart illustrating an exemplary method for managing an MBS according to various aspects. DETAILED DESCRIPTION

[0026] The present embodiment will now be described in detail with reference to the accompanying drawings, which are provided as illustrative examples of the embodiments so that those skilled in the art can practice the embodiments and substitutions that are obvious to those skilled in the art. It should be noted that the following figures and embodiments are not meant to limit the scope of the present embodiment to a single embodiment, but other implementations can be realized by interchanging some or all of the elements described or illustrated. In addition, in the case where certain elements of the present implementation can be partially or completely realized using known components, only those parts necessary for understanding the present implementation of such known components are described, and detailed descriptions of other parts of such known components are omitted so as not to obscure the present implementation. The embodiments described as being implemented in software should not be limited thereto, but may include embodiments implemented in hardware, or a combination of software and hardware, and vice versa, as is apparent to those skilled in the art, unless otherwise provided herein. In this specification, the implementation of a single component is shown and should not be considered as restrictive. On the contrary, the present disclosure is intended to cover other embodiments including a plurality of identical components, and vice versa, unless otherwise expressly provided herein. In addition, the applicant does not intend to give rare or special meanings to any term in the specification or claims, unless expressly stated so. Further, the present implementations encompass current and future known equivalents to the known components mentioned herein by way of illustration.

[0027] In MBS deployment scenarios, cell congestion may occur frequently, considering that the number of terminals or user equipment (UE) connected to the same cell and the amount of services carried by the cell are limited. The resulting cell congestion may result in the rejection and / or reduction of transmission of other services and / or UEs, thereby negatively affecting the user experience.

[0028] In 5G NR, the UE has three radio resource control (RRC) states: RRC connected state (RRC_CONNECTED), RRC idle state (RRC_IDLE), and RRC inactive state (RRC_INACTIVE). The RRC inactive state is a state defined in 5G NR. For example, when the UE enters the RRC inactive state, the UE retains part of the context of the access network. The core network may not be aware that the UE transitions to the RRC inactive state. That is, the RRC inactive state may be transparent to the core network.

[0029] In the RRC inactive state, the UE transitions from the RRC inactive state to the RRC connected state through a connection recovery process to send or receive data. The RRC inactive state not only saves energy, but also manages the delay of the control plane (for example, compared to a UE in the RRC idle state, the UE can quickly enter the RRC connected state with a lower control plane (CP) delay).

[0030] In some implementations involving MBS multicast reception in cell congestion and / or power saving situations, for some UEs applying MBS multicast, the RRC state may be converted to an RRC inactive state. Such UEs are converted from an RRC connected state to an RRC inactive state to receive or continue to receive a multicast session.

[0031] In some implementations, a point-to-multipoint (PTM) configuration delivery method is specified. For multicast services or multicast sessions, dedicated signaling is used. For broadcast services or broadcast sessions, only broadcast signaling (e.g., System Information Block (SIB) and MBS Control Channel (MCCH)) is used. For broadcast reception in other secondary cells (SCells), dedicated signaling for delivering system information may be used. When in RRC inactive state, the UE may receive multicast data or information.

[0032] The solution of the present application relates to enabling a UE to receive or continue to receive a multicast service in an RRC inactive state. In order to receive a multicast service, the UE needs to obtain a correct configuration, which is referred to herein as, for example, a PTM configuration, a multicast configuration, or an MBS configuration, and these names are interchangeable. The PTM configuration includes at least information in the access layer for the UE to obtain multicast data. Multicast service and multicast session can be used interchangeably to identify a multicast service in the context of a Radio Access Network (RAN).

[0033] Figure 1An exemplary wireless communication network 100 is shown. The wireless communication network 100 corresponds to a group communication or multicast service within a cellular network. In the wireless communication network 100, the network-side communication node or base station (Base Station, BS) may include one or more of a next-generation Node B (gNB), an E-Utran Node B (also known as an evolved Node B, eNodeB or eNB), a micro-micro station, a femto-micro station, a transmission / reception point (Transmission / Reception Point, TRP), an access point (Access Point, AP), etc. The terminal-side node or UE may include a long-range communication system (such as but not limited to a mobile device, a smart phone, a personal digital assistant (Personal Digital Assistant, PDA), a tablet computer, a laptop computer) or a short-range communication system (such as but not limited to a wearable device, a vehicle with a vehicle communication system, etc.). As shown in Figure 1 In the embodiment, BS 102 represents a network-side communication node, and UE 104a or 104b represents a terminal-side communication node. In some examples, BS 102 is sometimes referred to as a "wireless communication node", and UE 104a / 104b is sometimes referred to as a "wireless communication device".

[0034] like Figure 1 As shown, BS 102 can provide wireless communication services to UE 104a and 104b in cell 101. UE 104a can communicate with BS 102 via communication channel 103a. Similarly, UE 104b can communicate with BS 102 via communication channel 103b. The communication channels (e.g., 103a and 103b) can be through an interface, such as but not limited to the Uu interface also known as the universal mobile telecommunication system (UMTS) air interface. BS 102 is connected to a core network (CN) 108 via an external interface 107 (e.g., an NG interface).

[0035] Figure 2 1 is a block diagram of an exemplary wireless communication system 150 for transmitting and receiving downlink and uplink communication signals according to some aspects of the present disclosure. Figure 1 and 2 , system 150 is part of network 100. In system 150, it is possible to Figure 1 The wireless communication network 100 may be used to send and receive data symbols in a wireless communication environment.

[0036] System 150 generally includes BS 102 and UE 104a and 104b. BS 102 includes BS transceiver module 110, BS antenna 112, BS memory module 116, BS processor module 114, and network communication module 118. Modules / components are coupled to and interconnected with each other via data communication bus 120 as needed. UE 104a includes UE transceiver module 130a, UE antenna 132a, UE memory module 134a, and UE processor module 136a. Modules / components are coupled to and interconnected with each other via data communication bus 140a as needed. Similarly, UE 104b includes UE transceiver module 130b, UE antenna 132b, UE memory module 134b, and UE processor module 136b. Modules / components are coupled to and interconnected with each other via data communication bus 140b as needed. BS 102 communicates with UEs 104a and 104b via communication channel 155, which may be any wireless channel or other medium known in the art suitable for data transmission as described herein.

[0037] The system 150 may further include Figure 2 Modules / elements of any number other than the modules / elements shown in . The different illustrative blocks, modules, elements, circuits and processing logic described in conjunction with the arrangement disclosed herein can be implemented in hardware, computer-readable software, firmware or any actual combination thereof. In order to clearly illustrate this interchangeability and compatibility of hardware, firmware and software, different illustrative components, blocks, modules, circuits and steps are generally described according to their functions. Whether these functions are implemented as hardware, firmware or software depends on specific applications and the design constraints imposed on the entire system. The technician who is familiar with the concept described herein can implement such functions in an appropriate manner for each specific application, but such implementation decisions should not be interpreted as limiting the scope of the present disclosure.

[0038] The wireless transmission from the antenna of each of UE 104a and 104b to the antenna of BS102 is called uplink transmission, and the wireless transmission from the antenna of BS102 to the antenna of each of UE 104a and 104b is called downlink transmission. According to some schemes, each of UE transceiver modules 130a and 130b can be referred to as uplink transceiver or UE transceiver here. The uplink transceiver may include a transmitter circuit and a receiver circuit, each of which is coupled to respective antennas 132a and 132b. Alternatively, a duplex switch may couple the uplink transmitter or receiver to the uplink antenna in a time duplex mode. Similarly, BS transceiver module 110 may be referred to as a downlink transceiver or BS transceiver here. The downlink transceiver may include an RF transmitter circuit and a receiver circuit each coupled to antenna 112. The downlink duplex switch may selectively couple the downlink transmitter or receiver to antenna 112 in a time duplex mode. Operation of the transceivers 110, 130a, and 130b are coordinated in time such that uplink receivers are coupled to antennas 132a and 132b for receiving transmissions over the wireless communication channel 155 while downlink transmitters are coupled to antenna 112. In some examples, UEs 104a and 104b can communicate with BS 102 via the wireless communication channel 155 using UE transceivers 130a and 130b through respective antennas 132a and 132b. The wireless communication channel 155 can be any wireless channel or other medium suitable for downlink (DL) and / or uplink (UL) transmission of data as described herein.

[0039] The UE transceiver 130a / 130b and the BS transceiver 110 are configured to communicate via a wireless data communication channel 155 and cooperate with an appropriately configured antenna arrangement capable of supporting a specific wireless communication protocol and modulation scheme. In some examples, the UE transceiver 130a / 130b and the BS transceiver 110 are configured to support industrial standards such as Long Term Evolution (LTE) and emerging 5G standards. However, it should be understood that the present disclosure is not necessarily limited to the application of specific standards and associated protocols. Instead, the UE transceiver 130a / 130b and the BS transceiver 110 may be configured to support alternative or additional wireless data communication protocols, including future standards or variations thereof.

[0040] The processor modules 136a and 136b and 114 may each be implemented or implemented with a general purpose processor, a content addressable memory, a digital signal processor, an application specific integrated circuit, a field programmable gate array, any suitable programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof, designed to perform the functions described herein. In this manner, the processor may be implemented as a microprocessor, a controller, a microcontroller, a state machine, etc. The processor may also be implemented as a combination of computing devices, for example, a combination of a digital signal processor and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a digital signal processor core, or any other such configuration.

[0041] In addition, the methods or algorithms described in conjunction with the arrangements disclosed herein may be directly embodied in hardware, firmware, software modules executed by processor modules 114, 136a and 136b, respectively, or any practical combination thereof. Memory modules 116, 134a, 134b may be implemented as RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, removable disk, CD-ROM, or another suitable form of storage medium. In this regard, memory modules 116, 134a and 134b may be coupled to processor modules 114, 136a and 136b, respectively, so that processor modules 114, 136a and 136b may read information from memory modules 116, 134a and 134b, respectively, and write information to memory modules 116, 134a and 134b. Memory modules 116, 134a and 134b may also be integrated into their respective processor modules 114, 136a and 136b. In some examples, the memory modules 116, 134a, and 134b may each include a cache memory for storing temporary variables or other intermediate information during the execution of instructions to be executed by the processor modules 114, 136a, and 136b, respectively. The memory modules 116, 134a, and 134b may also each include a non-volatile memory for storing instructions to be executed by the processor modules 114, 136a, and 136b, respectively.

[0042] The network interface 118 generally represents the hardware, software, firmware, processing logic and / or other components of the BS 102, which implement bidirectional communication between the BS transceiver 110 and other network components and communication nodes configured to communicate with the BS 102. For example, the network interface 118 can be configured to support Internet or WiMAX services. In a typical deployment, the network interface 118 provides an 802.3 Ethernet interface so that the BS transceiver 110 can communicate with a computer network based on traditional Ethernet. In this way, the network interface 118 may include a physical interface for connecting to a computer network (e.g., a mobile switching center (MSC)). The term "configured for" or "configured for" as used herein with respect to a specified operation or function refers to a device, component, circuit, structure, machine, signal, etc. that is physically constructed, programmed, formatted and / or arranged to perform a specified operation or function. The network interface 118 can allow the BS 102 to communicate with other BSs or core networks via a wired or wireless connection.

[0043] BS102 may communicate with multiple UEs (including UE 104a and 104b) using multicast or broadcast (collectively referred to as MBS). Multiple UEs may each receive MBS services via multicast and / or broadcast. In order to receive MBS services, multiple UEs have a common understanding of the configuration of the MBS services, including but not limited to the frequency resource range for resource allocation, scrambling sequence, etc., referred to herein as PTM configuration, multicast configuration, or MBS configuration. The network (e.g., BS102 or cell 101) may deliver PTM configuration for MBS multicast reception in different RRC states for UE 104a or 104b.

[0044] In some examples, UE 104a or 104b receives the PTM configuration or its update from the network (e.g., BS 102 or cell 101) via dedicated signaling dedicated to the UE. An embodiment of the dedicated signaling includes RRC reconfiguration signaling. For example, when the UE is in an RRC inactive state, the UE initiates an RRC connection recovery procedure to receive a PTM configuration update. When the UE is in an RRC connected state, the PTM configuration is delivered by the network via dedicated signaling.

[0045] Figure 3 FIG. 3 is a flow chart showing a method 300 for managing an MBS according to different schemes. Figure 1-3 The method 300 may be performed by a network (eg, BS 102) and one of UEs 104a or 104b. The communication between the UE and the BS is performed on a channel in channels 103a, 103b, or 155, respectively. Figure 3 As shown by the dotted line in .

[0046] At step 305, when the UE is in the RRC connected state, the network (e.g., BS 102) sends the PTM configuration for each of the multiple MBSs to the UE using signaling specific to the UE (e.g., dedicated signaling). At 310, when the UE is in the RRC connected state, the UE receives the PTM configuration for each of the multiple MBSs using signaling specific to the UE. Thus, for the UE in the RRC connected state, the PTM configuration is delivered to the UE through dedicated signaling.

[0047] At step 315, when the UE is in the RRC connected state, the network transmits data corresponding to a plurality of MBSs using the PTM configuration received at 310. At 320, when the UE is in the RRC connected state, the UE receives data corresponding to a plurality of MBSs from the network using the PTM configuration.

[0048] In step 325, the network releases the UE to the RRC inactive state. For example, the network sends a signaling or message to the UE indicating that the UE will be released to the RRC inactive state. In step 330, the UE transitions from the RRC connected state to the RRC inactive state.

[0049] In order to continue multicast reception on some MBSs (referred to as at least one MBS) that the UE has received since the RRC connected state (e.g., in step 320), the corresponding PTM configuration is retained, which includes the MRB and the low-layer configuration of the multicast session associated with the at least one MBS. For example, in step 335, the UE retains the PTM configuration for the at least one MBS. In some embodiments, the at least one MBS may be some but not all of the multiple MBSs. In other embodiments, the at least one MBS may be all of the multiple MBSs.

[0050] At step 340, when the UE is in the RRC inactive state, the network sends at least one MBS using the reserved PTM configuration. At step 345, when the UE is in the RRC inactive state, the UE receives at least one MBS using the reserved PTM configuration.

[0051] In step 350, when the UE is in an RRC inactive state, the UE may determine a triggering event. In some embodiments, the network may initiate paging to notify the UE of a triggering event, such as a modification to the retained PTM configuration (including multicast session inactivation, activation, suspension, release, recovery, update, etc.). In some embodiments, the triggering event includes the UE detecting that the multicast reception quality has dropped by more than a certain threshold, so that the UE initiates an RRC connection recovery process through dedicated signaling to update the retained PTM configuration. In response to the triggering event, the UE modifies the retained PTM configuration based on signaling specific to the UE (dedicated signaling). An embodiment of the UE-specific signaling includes an RRC reconfiguration message or an RRC release message that is sent separately to the UE and has UE-specific content.

[0052] Figure 4 A flow chart of an exemplary method 400 for managing an MBS according to various aspects is shown. Figure 1-4 The method 400 may be performed by one of the UEs 104a or 104b. The method 300 is a specific implementation of the method 400.

[0053] At step 410, when the UE is in the RRC connected state, the UE receives the PTM configuration for each of the plurality of MBSs using signaling specific to the UE. Thus, for the UE in the RRC connected state, the PTM configuration is delivered to the UE through dedicated signaling.

[0054] At step 420, the UE transitions from the RRC connected state to the RRC inactive state. At 430, in response to transitioning to the RRC inactive state, the UE receives data for at least one of the plurality of MBSs using the PTM configuration received in the RRC connected state when the UE is in the RRC inactive state.

[0055] In some examples, method 400 further includes the UE determining a triggering event while in an RRC inactive state. In response to determining the triggering event, the UE modifies the PTM configuration to the UE.

[0056] Figure 5 is a flow chart illustrating an exemplary method 500 for managing an MBS according to various aspects. Figure 1-5 The method 500 may be performed by a network (eg, BS 102 ). The method 300 is a specific implementation of the method 500 .

[0057] At step 510, when the UE is in the RRC connected state, the network sends the PTM configuration for each of the multiple MBSs to the UE using UE-specific signaling. Thus, for the UE in the RRC connected state, the PTM configuration is delivered to the UE through dedicated signaling.

[0058] At step 520, the network releases the UE from the RRC connected state to the RRC inactive state. At 530, when the UE is in the RRC inactive state, the network transmits data for at least one MBS of the plurality of MBSs using the PTM configuration transmitted when the UE is in the RRC connected state.

[0059] In some examples, method 500 further includes, when the UE is in an RRC inactive state, the network sending an updated PTM configuration for at least one MBS to the UE using UE-specific signaling or broadcast signaling.

[0060] In some examples, regarding continuing to receive at least one MBS that is a subset of multiple MBSs received when the UE is in an RRC connected state when the UE is in an RRC inactive state, at least one MBS to be received or continued to be received in the RRC inactive state is identified. That is, when the UE is in an RRC inactive state, not all of the multiple MBSs need to be or can be received. The at least one MBS is a subset of multiple MBSs received when the UE is in an RRC connected state configured using PTM.

[0061] For example, when the UE is in the RRC inactive state, the network (e.g., BS 102) cannot adaptively adjust the configuration according to the reception quality of the UE (compared to a UE in an RRC connection). Therefore, when the UE is in the RRC inactive state, an MBS with a high quality of service (QoS) requirement is not sent to the UE. The selection of at least one MBS may be determined by the UE or by the BS 102.

[0062] In some examples, the UE determines whether it can receive the MBS in the RRC inactive state based on one or more conditions. In this regard, the method 400 further includes the UE selecting at least one MBS from the multiple MBSs based on the QoS requirement of each of the multiple MBSs.

[0063] These factors may include whether the PTM configuration of the MBS includes a mechanism for high QoS requirements. In an example where the PTM configuration of the MBS includes a mechanism for high QoS, the MBS is suspended in an RRC inactive state. On the other hand, in an example where the PTM configuration of the MBS does not include any mechanism for high QoS, the MBS continues to be received in an RRC inactive state. Factors for determining high QoS requirements include at least one of the following: whether hybrid automatic repeat request (HARQ) feedback is configured for each of a plurality of MBSs, whether an acknowledgement mode (AM) of a radio link control (RLC) is configured for at least one MBS radio bearer (MRB) for each of a plurality of MBSs; or whether a packet data convergence protocol (PDCP) status report is configured for at least one MRB for each of the plurality of MBSs. That is, the UE considers whether the PTM configuration includes a mechanism for high QoS requirements by considering whether HARQ feedback is configured, whether an RLC AM mode exists for a configured MRB, whether a PDCP status report is configured for certain MRBs, and the like. In some embodiments, the HARQ feedback configured for the MBS indicates that the MBS has a high QoS requirement. In some embodiments, enabling AM of RLC for MBS indicates that the MBS has high QoS requirements. In some embodiments, enabling PDCP status report for MBS indicates that the MBS has high QoS requirements.

[0064] In some embodiments, in response to determining that each of the at least one PTM configuration satisfies the condition to be retained (e.g., lack of a high QoS mechanism), the PTM configuration of the corresponding MBS session (e.g., at least one MBS) is retained (not suspended) in response to 330, and data for the at least one MBS may be received in an RRC inactive state. In some embodiments, in response to determining that the MRB of each of the at least one PTM configuration satisfies the condition to be retained (e.g., lack of a high QoS mechanism), the corresponding low layer configuration of the corresponding MBS session (e.g., at least one MBS) is retained (not suspended) in response to 330, and at least one MBS of the corresponding MBS multicast session may be received in an RRC inactive state.

[0065] In some embodiments, the network (e.g., BS 102) determines whether an MBS can be received in an RRC inactive state based on one or more conditions. For example, when the UE is in an RRC inactive state, the network may determine to stop sending an MBS or its session with low QoS requirements, for example, without data transmission, intermittent data transmission, or temporary data transmission. In order to reduce the energy consumption of the UE monitoring an MBS with low QoS requirements, when the UE is RRC-inactive, the network may indicate to the UE whether to send the MBS to the UE. In other words, when the UE is in an RRC inactive state so that the UE receives MBS data or continues to receive multicast data, the indication from the network to the UE may selectively indicate which MBS or MRB the UE needs. Therefore, the method 400 further includes receiving, by the UE, an indication identifying at least one MBS from the base station, wherein in response to receiving the indication, the at least one MBS is received or continues to be received in the RRC inactive state. The method 500 further includes: when the UE is in an RRC inactive state, the network determines to send at least one MBS to the UE or continue to send at least one MBS to the UE, and the network sends the indication identifying at least one MBS to the UE.

[0066] In some examples, the network may send the indication via RRC signaling. In some embodiments, the RRC signaling includes RRC reconfiguration. The RRC reconfiguration signaling or message includes: when the UE is in an RRC inactive state, indication information of retaining the retained PTM configuration for the at least one MBS. In other words, after the UE receives an RRC release with a suspended configuration and transitions to an RRC inactive state at 330, the UE retains the retained PTM configuration, which includes all multicast MRBs or some MRBs indicated in the RRC reconfiguration and the corresponding low-layer configuration of the corresponding MBS session. The UE receives or continues to receive data for the corresponding at least one MBS in the RRC inactive state.

[0067] In some embodiments, the indication identifying the retained PTM configuration may be per MBS or per MRB. In other words, the indication may identify each of at least one MBS (the indication information may include a list of MBS identifiers, such as a temporary mobile group identifier (TMGI)), or identify each MRB to be used for at least one MBS. If such indication is per MRB, the UE retains only the indicated MRB and the low-level configuration of at least one MBS identified when in the RRC inactive state. That is, other MRBs of the PTM configuration are suspended when transitioning to the RRC inactive state. If such indication is based on each MBS, all MRBs and low-level configurations of at least one MBS identified by the indication are retained when transitioning to the RRC inactive state. When transitioning to the RRC inactive state, no MRB associated with at least one MBS identified in the indication is suspended.

[0068] In some embodiments, the RRC signaling includes an RRC version that includes a list of indication information about which PTM configuration (referred to as at least one MBS) is retained when the UE is in an RRC inactive state. The indication information may include a list of MBS identifiers, such as a temporary mobile group identity (TMGI). In response to the UE receiving an RRC release with a suspension configuration from the network (e.g., in step 325), the UE does not suspend any MRB associated with at least one MBS in the list, and will not reset the HARQ process and related timers associated with at least one MBS. The UE receives or continues to receive data for at least one MBS in the RRC inactive state. In some embodiments, the network provides a list of MRBIDs and a multicast service list in the RRC release signaling or message. The UE retains only the indicated MRBs and suspends other MRBs.

[0069] Thus, the indication is received by the UE through RRC reconfiguration or RRC release. The indication includes an indication for each MBS in a plurality of MBSs or for each MRB associated with a plurality of MBSs. The indication includes a list of at least one MBS or at least one MRB to be retained when the UE is in an RRC inactive state. In some embodiments, in response to transitioning to an RRC inactive state, the UE performs at least one of the following: maintaining (e.g., not suspending) the indicated at least one MRB, stopping all running timers except a multicast discontinuous reception (DRX) timer for the indicated at least one MBS, refreshing soft buffers for all downlink HARQ processes except a downlink HARQ process for the indicated at least one MBS, or continuing to monitor a group radio network temporary identifier (G-RNTI) corresponding to the indicated at least one MBS.

[0070] In some examples, the triggering event includes a network (e.g., BS102) sending a notification to a UE. In response to receiving the notification, the UE modifies the PTM configuration for at least one MBS. In some embodiments, the notification includes paging. The network may apply a group paging mechanism for notifying multiple UEs via paging. The paging payload of the paging contains a list of MBS session IDs that the UE has joined, e.g., a list of TMGIs. The notification further includes a notification event associated with the MBS session ID.

[0071] For a UE receiving MBS in an RRC inactive state, triggering events or conditions for group paging include MBS suspension, MBS resumption, MBS inactivity, MBS activation, MBS release, or PTM configuration update to reduce unnecessary monitoring energy consumption and reduce the frequency of RRC state transitions.

[0072] For MBS suspension, the notification indicates that one MBS of at least one MBS is to be suspended. Modifying the PTM configuration includes that when the UE is in an RRC inactive state, the UE stops monitoring the one MBS, and when the UE is in an RRC inactive state, the UE suspends the PTM configuration corresponding to the one MBS. For example, a radio access network (RAN) node suspends the transmission of the MBS. Therefore, the UE does not need to resume the RRC connection to receive the suspension configuration, but is able to remain in the RRC inactive state to suspend the MBS reception configuration by, for example, suspending the associated MRB and stopping MBS data reception in the MAC and physical layers (for example, stopping the G-RNTI for MBS monitoring).

[0073] When the UE is in the RRC inactive state, if no data is temporarily sent in the RAN, the monitoring of MBS data will cause unnecessary power consumption. In order to improve power efficiency, the network can use the group paging function (e.g., notification) to notify the UE that certain MBSs are suspended or instruct the UE to stop monitoring such MBSs and suspend the associated PTM configuration (i.e., without releasing the configuration). In one embodiment, indication information (e.g., 1-bit indication) is associated with the MBS session identifier in the group paging payload, which indicates that the MBS session has been suspended. Upon receiving such a group paging, the UE stops monitoring the MBS data and suspends the associated PTM configuration. In one embodiment, if there is no such indication information, the UE initiates a traditional RRC connection recovery process and transitions to the RRC connected state.

[0074] Regarding MBS resumption, the network resumes transmission of the MBS. Therefore, the UE resumes the associated MRB and resumes G-RNTI monitoring of the resumed MBS while remaining in the RRC inactive state. Therefore, the notification indicates resumption of one MBS. Modifying the PTM configuration includes: when the UE is in the RRC inactive state, the UE resumes the PTM configuration corresponding to the one MBS; and when the UE is in the RRC inactive state, the UE uses the PTM configuration to receive the one MBS.

[0075] To improve power efficiency, certain MBSs with low QoS that temporarily have no data for the UE may be suspended when the UE is in the RRC inactive state. The network may use a group paging function (e.g., notification) to resume reception of such MBSs. In one embodiment, an indication message (e.g., a 1-bit indication) is associated with an MBS session identifier in a group paging payload, indicating that the MBS session has been resumed. Upon receiving such a group paging, the UE resumes the corresponding MBS MRB and low-layer configuration of the MBS session and starts multicast data monitoring. In one embodiment, if there is no such indication message, the UE initiates a conventional RRC connection resumption procedure and transitions to the RRC connected state.

[0076] Regarding MBS deactivation, in response to receiving MBS deactivation signaling from the core network, the RAN node releases MBS radio resources and stops MBS transmission. In response to receiving a notification indicating a deactivated MBS, the UE releases the associated PTM configuration (e.g., MRB and PTM configuration in the lower layer) and stops multicast reception. Therefore, the notification indicates that one of the at least one MBS will be deactivated. Modifying the PTM configuration includes when the UE is in an RRC deactivated state, the UE stops listening to the one MBS, and when the UE is in an RRC deactivated state, the UE releases the PTM configuration corresponding to the one MBS.

[0077] If there is no data for the MBS being sent and the MBS is deactivated in the network, monitoring MBS data for a UE in an RRC deactivated state results in unnecessary power consumption. Although the network can also notify the UE to resume the RRC connection, this may result in more signaling overhead. In order to improve power efficiency, the network uses a group paging function (e.g., notification) to notify the UE that certain MBSs are deactivated. Upon receiving the indication, the UE stops monitoring such MBSs and releases the associated PTM configuration.

[0078] In one embodiment, an indication message (e.g., a 1-bit indication) is associated with the MBS session identifier in the group paging payload, indicating that the MBS session has been deactivated. Upon receiving such a group paging, the UE stops monitoring the MBS data and releases the associated PTM configuration. In one embodiment, if there is no such indication message, the UE initiates a conventional RRC connection recovery procedure and transitions to the RRC connected state.

[0079] Regarding PTM configuration update. The network may update the PTM configuration of a specific MBS in the at least one MBS. If the network updates the PTM configuration (e.g., the network reallocates radio resources for the MBS), the UE may need to frequently switch states between the RRC-inactive and RRC-connected states, which results in unnecessary power consumption and signaling overhead. In order to improve power and air interface resource efficiency, the network uses a group paging function (e.g., notification) to notify the UE that certain multicast PTM configurations are updated and / or indicate the delivery method of the updated configuration (i.e., RRC dedicated signaling or MCCH).

[0080] In one embodiment, an indication information (e.g., a 1-bit indication) is associated with an MBS session identifier in a group paging payload, indicating that the PTM configuration of the MBS session has been updated. Upon receiving such a group paging, the UE initiates an RRC connection recovery procedure, and a recovery cause value may be added to indicate that the reason for the recovery is to update the PTM configuration. BS102 may add the PTM configuration in an RRC message (e.g., RRC release). Upon receiving the RRC message, the UE updates the PTM configuration of the associated MBS and continues to receive data for the MBS in an RRC inactive state. In some embodiments, the notification indicates that the PTM configuration for one of the at least one MBS will be updated. Modifying the PTM configuration includes the UE initiating an RRC connection recovery procedure, and in response to initiating the RRC connection recovery procedure, the UE receives indication information for one of the at least one MBS from the network. In some embodiments, the UE receives an updated PTM configuration for one of the at least one MBS, and the UE receives data corresponding to the updated PTM configuration from the network. In some embodiments, the indication information is an updated PTM configuration and is received by the UE through an RRC version. Thus, when the UE initiates the RRC connection recovery process, in some embodiments, the updated PTM configuration is sent to the UE via RRC release. In other embodiments, the UE initiates the RRC connection recovery process and actually enters the RRC connected state to receive the update. In one embodiment, the indication information is the updated PTM configuration, the UE in the RRC recovery message indicates the MBS session ID, or uses the MBS session ID as the UE contention resolution identifier in the random access process. In the following RRC release message, it includes the updated PTM configuration.

[0081] In another embodiment, indication information (e.g., a 1-bit indication) is associated with the MBS session identifier in the group paging payload, indicating that the PTM configuration of the MBS session has been updated. Upon receiving such a group paging, the UE updates the PTM configuration obtained from the broadcast signaling (e.g., MCCH) and continues to receive data for the MBS in an RRC inactive state. In some embodiments, the network sends indication information to the UE via an RRC version to instruct the UE to obtain an updated PTM configuration from the broadcast signaling (e.g., MCCH). The updated PTM configuration UE receives from the broadcast signaling (e.g., MCCH).

[0082] In another embodiment, if there is no such indication information, the UE initiates a traditional RRC connection recovery process and switches to the RRC connected state.

[0083] The network may send a notification indicating a modification of the PTM configuration of at least one MBS using signaling such as group paging associated with the MBS session ID list in the paging payload. Depending on the supported functionality, the notification may have different lengths. For example, if only suspend and resume need to be indicated, one bit is required. If all suspend, resume, inactive, and update functions need to be supported, two bits are required.

[0084] In some examples, when the UE is in an RRC inactive state, the update of the PTM configuration may be triggered by a MAC CE. When the UE is in an RRC inactive state, the network may use a MAC CE to indicate the update of the PTM configuration (including suspension, resumption, inactivation, and update for certain MBSs).

[0085] In one embodiment, a MAC CE including indication information identified by a corresponding logical channel ID (LCID) is sent by the network to the UE (eg, by multiplexing with multicast data) to indicate one or more of suspension, resumption, deactivation and update of a certain MBS.

[0086] Regarding MBS suspension, the RAN node (e.g., BS 102) suspends the transmission of the MBS. Therefore, the UE does not need to resume the RRC connection to receive the suspension configuration, but instead remains in the RRC inactive state to suspend the MBS reception configuration, for example, by suspending the associated MRBs in the MAC and physical layers and stopping MBS data reception. For example, the UE may stop the G-RNTI for multicast service monitoring.

[0087] For MBS resumption, the network resumes the transmission of MBS. Therefore, the UE resumes the associated MRB and resumes G-RNTI monitoring while remaining in the RRC inactive state.

[0088] Regarding MBS deactivation, in response to receiving MBS deactivation signaling from the core network, the RAN node (e.g., BS 102) releases MBS radio resources and stops MBS transmission. In response to receiving such an indication, the UE releases the associated PTM configuration (e.g., MRB and PTM configuration in the lower layer) and stops MBS reception.

[0089] For PTM configuration update, the network may update the PTM configuration of certain MBSs. In response to receiving a MACCE indicating an update, the UE initiates an RRC connection recovery procedure and adds a recovery cause value to indicate that the reason for resuming the RRC is an update of the PTM configuration of the MBS.

[0090] In some embodiments, the network may transmit a MAC CE to the UE via a PTM identified by a corresponding G-RNTI associated with the MBS.

[0091] Thus, in some examples, determining a triggering event includes receiving a MAC CE from the network when the UE is in an RRC inactive state, the MAC CE indicating that a PTM configuration for one of the at least one MBS is to be modified. The MAC CE includes a service ID or service index of the one MBS. Modifying the PTM configuration includes one of MBS suspension, MBS resumption, MBS inactivation, or updating the PTM configuration.

[0092] In some settings, when the UE is in an RRC inactive state, the RRC connection recovery process is triggered when the MBS reception quality drops to a certain threshold. The MBS reception quality can be determined by BS102 or the UE. For example, the UE can measure at least one of the reference signal received power (RSRP) or reference signal received quality (RSRQ) of the configured measurement resources, the packet loss rate (e.g., in the Packet Data Convergence Protocol (PDCP)), or the block error rate (BLER) in layer 1. The network (e.g., BS102) can indicate the relevant threshold in dedicated signaling to the UE, or alternatively, the UE can determine the relevant threshold. Thus, in other words, the reception quality is determined based on at least one of the measured signal strength or packet loss rate.

[0093] When the UE is in the RRC inactive state, the UE continuously monitors these indicators (e.g., measured signal strength or packet loss rate) while receiving at least one MBS. In response to determining that the reception quality of the MBS has degraded to a threshold, the UE initiates an RRC connection recovery procedure. The UE sets the recovery cause value to indicate that the reason for initiating the RRC connection recovery procedure is that the reception quality has degraded.

[0094] In some embodiments, the network (e.g., BS102) can restore the RRC connection of the UE to update the PTM configuration or add the PTM configuration in a dedicated signaling (e.g., RRC version). Upon receiving such an RRC message, the UE updates the PTM configuration of the MBS and continues to receive data for the MBS in an RRC connected or RRC inactive state.

[0095] Thus, in some embodiments, determining a triggering event includes determining, by the UE when the UE is in an RRC inactive state, that a reception quality of one of the at least one MBS is below a threshold. Modifying the PTM configuration includes initiating, by the UE, the RRC connection recovery procedure and adding a recovery cause value to indicate initiating the RRC connection recovery procedure to update the PTM configuration for the one MBS. In addition, the UE receives an updated PTM configuration for the one MBS from the network. The UE receives an MBS from the network using the updated PTM configuration.

[0096] In some examples, when the UE is in an RRC inactive state, in order to reduce the frequency of state transitions caused by PTM configuration updates, the PTM configuration can be delivered in an RRC release. Therefore, modifying the PTM configuration for at least one MBS includes receiving an updated PTM configuration in an RRC release signaling, wherein the updated PTM configuration includes at least one of a multicast configuration and a broadcast configuration. The form of the PTM configuration in the RRC version includes, but is not limited to, a multicast configuration carried in a UE-specific RRC reconfiguration, or a broadcast PTM configuration carried in the MCCH of multiple UEs. For example, Figure 6 is a table illustrating an embodiment PTM configuration carried in a dedicated RRC reconfiguration dedicated to a UE according to some aspects. Figure 7 A table showing an embodiment broadcast PTM configuration carried in MCCH according to some aspects.

[0097] In some examples, when UE 104a or 104b is in an RRC connected or RRC inactive state, the UE receives a PTM configuration or an update thereof from the network (e.g., BS 102 or cell 101) via broadcast signaling (e.g., MCCH). For example, when the UE is in an RRC connected state, the UE monitors broadcast signaling or MCCH to receive a PTM configuration or an update thereof for multicast. When the UE is in an RRC inactive state, the UE monitors broadcast signaling or MCCH to receive a PTM configuration or an update thereof for multicast, so that the UE does not need to restore the RRC connection to receive the PTM configuration or an update thereof.

[0098] In some examples, in order to minimize protocol modifications, the multicast PTM configuration carried in the MCCH may be the same as the broadcast PTM configuration, an example of which is shown in Figure 7 Shown in.

[0099] Figure 8 8 is a flow chart illustrating an exemplary method 800 for managing an MBS according to various aspects. Figure 1-8The method 800 may be performed by a network (eg, BS 102) and one of UEs 104a or 104b. The communication between the UE and the BS is performed on a channel in channels 103a, 103b, or 155, respectively. Figure 8 As shown by the dotted line in .

[0100] In step 802, when the UE is in an RRC connected state, the network (e.g., BS 102) sends indication information indicating that a PTM configuration for each of the multiple MBSs is obtained from broadcast signaling. In step 804, the UE receives indication information indicating that a PTM configuration for each of the multiple MBSs is obtained from broadcast signaling, wherein the broadcast signaling is received when the UE is in an RRC connected state.

[0101] At step 805, when the UE is in the RRC connected state, the network (e.g., BS 102) sends the PTM configuration for each of the multiple MBSs to the UE using broadcast signaling to the UE. At step 810, when the UE is in the RRC connected state, the UE receives the PTM configuration for each of the multiple MBSs using broadcast signaling. Thus, for the UE in the RRC connected state, the PTM configuration is delivered to the UE through broadcast signaling.

[0102] In step 815, when the UE is in the RRC connected state, the network transmits data corresponding to a plurality of MBSs using the PTM configuration received in step 810. In step 820, when the UE is in the RRC connected state, the UE receives data corresponding to a plurality of MBSs from the network using the PTM configuration.

[0103] At step 825, the network releases the UE to the RRC inactive state. For example, the network sends appropriate signaling, a message, or a notification indicating to the UE that the UE will be released to the RRC inactive state. At step 830, the UE transitions from the RRC connected state to the RRC inactive state.

[0104] In step 835, the UE monitors the broadcast signaling to obtain updates to the PTM configuration. In step 840, the network sends the updated PTM configuration via broadcast signaling. In step 845, the UE receives the updated PTM configuration via broadcast signaling. In step 850, the network sends at least one MBS using the updated PTM configuration. In step 855, the UE receives at least one MBS using the updated PTM configuration.

[0105] Fig. 9 is a flow chart illustrating an exemplary method 900 for managing an MBS according to various aspects. Figure 1-9, method 900 may be performed by one of UEs 104a or 104b. Method 800 is a specific implementation of method 900.

[0106] At step 910, when the UE is in an RRC connected state, the UE receives indication information indicating that a PTM configuration for each of the multiple MBSs is obtained from broadcast signaling. At step 920, when the UE is in an RRC connected state, the UE receives a PTM configuration for each of the multiple MBSs using broadcast signaling for receiving the multiple MBSs. The PTM configuration is used to receive the multiple MBSs when the UE is in an RRC connected state.

[0107] In some examples, method 900 further includes when the UE is in an RRC connected state, the UE receiving multiple MBSs from the network based on the PTM configuration. The UE transitions from the RRC connected state to an RRC inactive state. When the UE is in the RRC inactive state, the UE monitors broadcast signaling for PTM configuration. The UE receives the PTM configuration from the network using the broadcast signaling. The PTM configuration is used to receive at least one MBS when the UE is in the RRC inactive state. The UE receives at least one MBS from the network based on the PTM configuration.

[0108] Fig.10 is a flow chart illustrating an exemplary method 1000 for managing an MBS according to various aspects. Figure 1-10 The method 1000 may be performed by a network (eg, BS 102). The method 800 is a specific implementation of the method 1000.

[0109] In step 1010, the network (e.g., BS 102) sends indication information to the UE using UE-specific signaling, where the indication information indicates that when the UE is in an RRC connected state, the PTM configuration for each of the multiple MBSs is obtained from the broadcast signaling used to send the multiple MBSs, and when the UE is in an RRC inactive state, the PTM configuration for each of the multiple MBSs is obtained from the broadcast signaling used to send the multiple MBSs.

[0110] At step 1020, the network sends, to the UE using broadcast signaling, a PTM configuration for sending a plurality of MBSs when the UE is in an RRC connected state and a PTM configuration for sending at least one MBS when the UE is in an RRC inactive state.

[0111] In some examples, method 1000 further includes when the UE is in an RRC connected state, the network sending multiple MBSs based on the PTM configuration to the UE. The network releases the UE from the RRC connected state to an RRC inactive state. When the UE is in an RRC inactive state, the network sends at least one MBS to the UE based on the PTM configuration.

[0112] In some embodiments, there are multicast services with high QoS requirements and low QoS requirements. The PTM configuration of multicast through broadcast signaling (e.g., MCCH) lacks the flexibility of UE-level configuration, which may not provide high QoS requirements. For multicast services with high QoS requirements, dedicated signaling can be used to send PTM configuration to ensure reliability. For multicast services with low QoS requirements, even if the UE is in RRC connected state, the UE can obtain PTM configuration by monitoring MCCH signaling based on the scalability indication of the gNB.

[0113] In some examples, a method is provided to indicate that a PTM configuration is distributed to a UE via broadcast signaling, using an MCCH carrying a PTM configuration for a UE that needs to receive MBS and other auxiliary information, such as the service availability of an MBS service in a neighboring cell. The MCCH also uses a modification period, and only the MCCH content is allowed to be modified at each modification period boundary. The notification mechanism is used to announce changes in the MCCH content due to the start, modification or stop of a broadcast session and due to modification of neighboring cell information.

[0114] When the UE is in an RRC connected state, the UE obtains the PTM configuration by receiving the MCCH, which can be used when the UE is in an RRC inactive state. In this case, it would be beneficial to assist the UE to use some dedicated signaling to obtain the broadcast (e.g., MCCH) information to reduce power consumption and overall signaling overhead. The auxiliary information or indication information through dedicated signaling (e.g., UE-specific signaling) includes: (1) information indicating that the PTM configuration is through broadcast signaling (e.g., MCCH); (2) associated system information blocks (SIBs) required for receiving broadcast signaling (e.g., MCCH); and (3) related broadcast (e.g., MCCH) information, including information required to receive the PTM configuration.

[0115] Thus, the indication information is received using signaling dedicated to the UE (e.g., dedicated signaling). The indication information indicates that the UE is to obtain the PTM information from the broadcast signaling. The indication information includes at least one of information indicating that the PTM configuration of the at least one MBS is provided through the broadcast signaling, a SIB for receiving the configuration of the broadcast signaling, and broadcast signaling information including the PTM configuration of the multiple MBSs and / or the at least one MBS.

[0116] In some configurations, dedicated signaling (e.g., RRC reconfiguration) carries indication information, which indicates that the UE obtains the multicast PTM configuration or the update of the multicast PTM configuration by monitoring the MCCH in the RRC connected state. In other words, the indication information includes an indication indicating that at least one of the PTM configuration or the update of the PTM configuration is received via broadcast signaling. After receiving the indication information, the UE starts the MCCH process to receive multicast data, for example, receives the SIB to obtain the configuration information of the MCCH, and then obtains the relevant multicast PTM configuration information by monitoring the MCCH. The method also includes the UE monitoring the SIB message containing the configuration for receiving the broadcast signaling. The UE receives the broadcast signaling containing the PTM configuration or the update of the PTM configuration from the network. The UE receives data corresponding to at least one MBS from the network based on the updated PTM configuration.

[0117] In some configurations, dedicated signaling (e.g., RRC reconfiguration) carries an associated system information block message, which includes information required to receive the MCCH. The UE performs MCCH monitoring based on the information. In some embodiments, the SIB message explicitly indicates that for such an MBS, the UE obtains the PTM configuration by monitoring the MCCH rather than dedicated signaling. In the absence of such an indication, the UE assumes that the PTM configuration is delivered by a traditional configuration method (e.g., by dedicated signaling). Thus, the indication information includes the SIB message. The SIB message includes a configuration for receiving broadcast signaling. The indication information indicates that the PTM configuration or an update of the PTM configuration is obtained from the broadcast signaling. The SIB message is used to obtain a configuration for receiving broadcast signaling. Data corresponding to the MBS is received based on the PTM configuration. This mechanism reduces the delay in obtaining the associated SIB.

[0118] In some configurations, dedicated signaling (e.g., RRC reconfiguration) carries the MCCH content or the entire MCCH content for the MBS of interest to the UE, indicating that for such MBS, the corresponding PTM configuration is delivered through a method similar to MCCH. The UE then applies the multicast PTM configuration in the MCCH content, and after receiving the MCCH content, performs multicast data reception based on the information. The UE can monitor the MCCH and MCCH change notifications by itself after the MCCH monitoring process, or obtain the MCCH through other dedicated signaling containing MCCH content. The indication information includes broadcast signaling information, which includes the PTM configuration for at least one MBS. In some examples, broadcast signaling information including the PTM configuration for at least one MBS is received. Data corresponding to the at least one MBS is received based on the PTM configuration. This mechanism reduces the delay caused by monitoring the MCCH.

[0119] In some configurations, when the UE is in the RRC connected state, the UE periodically monitors the MCCH during the modification period to obtain the multicast PTM configuration. Compared with the dedicated signaling configuration, the scalability is improved, and if there are a large number of UEs in the cell occupying the same MBS, the air interface overhead caused by the configuration update is reduced. However, continuous monitoring of the MCCH also introduces additional power consumption, especially in the current MCCH modification notification mechanism, where the UE must monitor the MCCH change notification in each modification period. Even if the modification is for other MBSs in the cell (broadcast services and multicast services, if for RRC inactive UEs, the MCCH is also used for multicast services). Therefore, it is very likely that the UE monitors the MCCH, but the PTM configuration of its interest is not updated.

[0120] In some embodiments, in order to reduce power consumption and notify the UE of the PTM update of the multicast service, the network sends a short message with group paging to the UE. In response to receiving the short message indicating the PTM update of the MBS, the UE applies the MCCH acquisition process in the next modification. If the short message is not received, the UE does not perform the MCCH acquisition process. Thus, in some examples, the UE receives a short message indicating an update to the PTM configuration from the network. In response to receiving the short message, the UE performs an acquisition process (e.g., an MCCH acquisition process) to acquire broadcast signaling for receiving an update to the PTM configuration.

[0121] In some embodiments, in order to reduce power consumption of monitoring MCCH and changes in multicast services, in downlink control information (DCI), the network sends an indication to indicate whether there is an update or modification of the PTM configuration of the MBS. For UEs that are only interested in multicast services, if there is no such indication, the UE can ignore MCCH reception during the modification period. Thus, in some examples, the UE receives DCI broadcast signaling indicating an update to the PTM configuration from the network. In response to receiving the DCI, the UE performs an acquisition process to obtain broadcast signaling for receiving an update to the PTM configuration.

[0122] In some embodiments, when the UE is in the RRC connected state, the network can notify the UE through dedicated signaling (e.g., RRC signaling, MAC CE) to indicate that the PTM configuration of the multicast service UE is interested in is to be updated. In the current or next modification period, the UE monitors the MCCH transmission to receive the latest PTM configuration of the multicast service of interest. Thus, in some examples, the UE receives a MAC CE indicating an update to the PTM configuration from the network. In response to receiving the MAC CE, the UE performs an acquisition process to obtain broadcast signaling for receiving an update to the PTM configuration.

[0123] In some examples, when the UE is in an RRC connected state indicating an update to the PTM configuration, the UE receives update signaling specific to the UE from the network. In response to receiving the update signaling, the broadcast signaling is monitored in the current or next modification period for updates to the PTM configuration.

[0124] In some configurations, when the UE is in an RRC inactive state, if indication information is added for a UE in an RRC connected state, the indication information indicating obtaining a multicast PTM configuration from an MCCH, the UE in the RRC inactive state performs a method similar to the MCCH. For example, the UE receives indication information indicating receipt of a PTM configuration and an update to the PTM configuration from the network through broadcast signaling in both the RRC connected state and the RRC inactive state.

[0125] In some examples, UE 104a or 104b receives PTM configuration or updates thereof from the network (e.g., BS 102 or cell 101) via dedicated signaling and broadcast signaling (e.g., MCCH). For example, when the UE is in an RRC inactive state, the UE monitors broadcast signaling (e.g., MCCH) to receive PTM configuration or updates thereof for multicast. When the UE is in an RRC connected state, the UE receives PTM configuration from the network via dedicated signaling.

[0126] In some examples, when the UE is in an RRC connected state, the PTM configuration of the MBS is obtained from dedicated signaling. When the UE is in an RRC inactive state, the PTM configuration of the MBS is obtained from broadcast signaling (eg, MCCH).

[0127] Fig.11 1 is a flow chart illustrating an exemplary method 1100 for managing an MBS according to various aspects. Figure 1-11 The method 1100 may be performed by a network (eg, BS 102) and one of UEs 104a or 104b. The communication between the UE and the BS may be performed on a channel in channels 103a, 103b, or 155, respectively. Fig.11 As shown by the dotted line in .

[0128] At step 1105, when the UE is in the RRC connected state, the network (e.g., BS 102) sends the PTM configuration to the UE using a UE-specific first signaling (e.g., dedicated signaling) for each of the at least one MBS. At step 1110, when the UE is in the RRC connected state, the UE receives the PTM configuration for each of the at least one MBS using the UE-specific first signaling. Thus, for the UE in the RRC connected state, the PTM configuration is delivered to the UE through dedicated signaling.

[0129] In step 1115, when the UE is in the RRC connected state, the network transmits data corresponding to at least one MBS using the PTM configuration received in step 1110. In step 1120, when the UE is in the RRC connected state, the UE receives data corresponding to at least one MBS from the network using the PTM configuration.

[0130] In step 1125, the network sends indication information to the UE using a second signaling when the UE is in an RRC inactive state, the indication information indicating that the PTM configuration for receiving at least one MBS is obtained from the broadcast signaling when the UE is in an RRC inactive state. In step 1130, when the UE is in an RRC connected state, the UE receives indication information from the network using a second signaling specific to the UE, the indication information indicating that the PTM configuration for receiving at least one MBS is obtained from the broadcast signaling when the UE is in an RRC inactive state. In some embodiments, the first signaling and the second signaling are the same signaling. In other embodiments, the first signaling and the second signaling are different.

[0131] At step 1135, the network releases the UE to the RRC inactive state. For example, the network sends appropriate signaling, a message, or a notification indicating to the UE that the UE will be released to the RRC inactive state. At 1140, the UE transitions from the RRC connected state to the RRC inactive state.

[0132] In step 1145, the UE monitors broadcast signaling of a PTM configuration for any one of the at least one MBS or an update of the PTM configuration for any one of the at least one MBS. In step 1150, when the UE is in an RRC inactive state, the network sends the PTM configuration or an update of the PTM configuration via broadcast signaling. In step 1155, when the UE is in an RRC inactive state, the UE receives the PTM configuration or an update of the PTM configuration from the network via broadcast signaling.

[0133] At step 1160, when the UE is in the RRC inactive state, the network transmits at least one MBS using the updated PTM configuration. At step 1165, when the UE is in the RRC inactive state, the UE receives at least one MBS using the updated PTM configuration.

[0134] Fig.12 is a flow chart illustrating an exemplary method 1200 for managing an MBS according to various aspects. Figure 1-12 The method 1200 may be performed by one of the UEs 104a or 104b. The method 1100 is a specific implementation of the method 1200.

[0135] At step 1210, when the UE is in the RRC connected state, the UE receives the PTM configuration for each of the at least one MBS using the UE-specific first signaling. Thus, for the UE in the RRC connected state, the PTM configuration is delivered to the UE through dedicated signaling.

[0136] At step 1220, when the UE is in an RRC connected state, the UE receives indication information from the network using a second signaling specific to the UE, the indication information indicating that when the UE is in an RRC inactive state, a PTM configuration for receiving at least one MBS is obtained from a broadcast signaling. In some embodiments, the first signaling and the second signaling are the same signaling. In other embodiments, the first signaling and the second signaling are different.

[0137] In some examples, method 1200 further includes: when the UE is in an RRC inactive state, the UE receives a PTM configuration for receiving at least one MBS from the network using broadcast signaling; and when the UE is in an RRC inactive state, the UE receives the PTM configuration from the network from broadcast signaling.

[0138] The indication information includes at least one of information indicating that a PTM configuration of at least one MBS is provided through broadcast signaling, a SIB for receiving broadcast signaling, and broadcast signaling information including a PTM configuration of at least one MBS used in an RRC inactive state.

[0139] Fig.13 A flow chart of an exemplary method 1300 for managing an MBS according to various aspects is shown. Figure 1-13 , the method 1300 may be performed by a network (eg, BS 102 ). The method 1100 is a specific implementation of the method 1300 .

[0140] At step 1310, when the UE is in the RRC connected state, the network (e.g., BS 102) sends the PTM configuration to the UE using a UE-specific first signaling (e.g., dedicated signaling) for each of the at least one MBS. Thus, for the UE in the RRC connected state, the PTM configuration is delivered to the UE via dedicated signaling.

[0141] In step 1320, the network sends indication information to the UE using a second signaling when the UE is in an RRC inactive state, the indication information indicating that the PTM configuration for receiving at least one MBS is obtained from the broadcast signaling when the UE is in an RRC inactive state. In some embodiments, the first signaling and the second signaling are the same signaling. In other embodiments, the first signaling and the second signaling are different.

[0142] In some embodiments, the method 1300 further includes the network sending, using broadcast signaling, a PTM configuration to the UE for receiving at least one MBS when the UE is in an RRC inactive state, and the network sending an update to the PTM configuration to the UE when the UE is in an RRC inactive state.

[0143] Thus, when the UE is in the RRC connected state, the PTM configuration of the MBS is delivered through dedicated signaling. In response to the UE being released by the network to the RRC inactive state, in order to continue MBS reception, the PTM configuration is reacquired from the broadcast (eg, MCCH).

[0144] When the UE is in an RRC inactive state, it is beneficial to assist the UE in obtaining MCCH information by using some dedicated signaling (e.g., RRC reconfiguration, RRC release, etc.). This reduces power consumption and overall signaling overhead. The indication information through dedicated signaling includes at least one of information indicating that the MBS configuration is broadcast (e.g., MCCH), associated SIBs required for receiving the MCCH, and related MCCH information, including information required for receiving the MBS configuration.

[0145] In some embodiments, the RRC reconfiguration carries indication information, indicating that the UE obtains the multicast PTM configuration or the update of the multicast PTM configuration by monitoring the MCCH in the RRC inactive state. Thus, in some embodiments, the indication information includes an indication indicating that at least one of the PTM configuration of at least one MBS or the update of the PTM configuration is received through broadcast signaling. When the UE is in the RRC inactive state, the broadcast signaling is received and monitored by the UE in response to receiving the indication. The indication information is carried in the RRC reconfiguration message.

[0146] In one embodiment, in response to receiving the indication information and in response to the UE being released by the network to the RRC inactive state, in order to continue MBS reception, the corresponding PTM configuration (e.g., the associated MRB and the low-layer configuration of the multicast session) is temporarily retained. The UE starts a process similar to MCCH to receive MBS data in the RRC inactive state, for example, receiving SIB to obtain the configuration information of MCCH, and then obtains the relevant PTM configuration information by monitoring MCCH. Before obtaining the updated PTM configuration, the UE continues to apply the current PTM configuration to receive one or more of at least one MBS, wherein the current PTM configuration can be received when the UE is in the RRC connected state. Therefore, in response to receiving the indication, in response to the UE switching from the RRC connected state to the RRC inactive state, the UE retains the PTM configuration corresponding to one of the at least one MBS to continue receiving the one MBS. After the UE receives the PTM configuration through broadcast signaling in the RRC inactive state, the PTM configuration received in the RRC connected state is released.

[0147] For another example, when the UE receives the indication information and the network releases the UE to the RRC inactive state, the UE starts a process similar to the MCCH in the RRC inactive state to receive multicast data, such as receiving the SIB to obtain the configuration information of the MCCH, and then obtains the relevant multicast PTM configuration information by monitoring the MCCH. Therefore, in response to receiving the indication, the UE releases the PTM configuration corresponding to the MBS in the at least one MBS in response to the UE transitioning from the RRC connected state to the RRC inactive state, and receives the broadcast signaling for updating to the PTM configuration in response to the UE transitioning from the RRC connected state to the RRC inactive state.

[0148] In some configurations, the RRC version carries indication information, and the indication information instructs the UE to obtain the multicast PTM configuration or the update of the multicast PTM configuration by monitoring the MCCH in the RRC inactive state.

[0149] In response to transitioning from the RRC connected state to the RRC inactive state, the UE monitors a SIB message, the SIB message including a configuration for receiving broadcast signaling when the UE is in the RRC inactive state. When the UE is in the RRC inactive state, the UE receives broadcast signaling for obtaining a PTM configuration or an update of a PTM configuration for at least one MBS from the network. The UE receives data corresponding to the at least one MBS based on the updated PTM configuration.

[0150] In one embodiment, in response to the UE being released by the network to the RRC inactive state, in order to continue MBS reception, the corresponding PTM configuration (e.g., the associated MRB and the low-layer configuration of the multicast session) is temporarily retained. The UE initiates a process similar to MCCH to receive MBS data in the RRC inactive state, for example, receives SIB to obtain the configuration information of MCCH, and then obtains the relevant multicast PTM configuration information by monitoring MCCH. Therefore, in response to receiving the indication information, the UE retains the PTM configuration corresponding to one of the at least one MBS to continue to receive the one MBS in response to the UE switching from the RRC connected state to the RRC inactive state. After the UE receives the PTM configuration through broadcast signaling in the RRC inactive state, the PTM configuration received by the UE in the RRC connected state is released. Before obtaining the updated PTM configuration, the UE continues to apply the current PTM configuration to receive one or more of the at least one MBS, wherein the current PTM configuration can be received when the UE is in the RRC connected state.

[0151] For another example, when the UE is released to the RRC inactive state by the network, the UE starts a process similar to MCCH to receive MBS data in the RRC inactive state, such as receiving SIB to obtain MCCH configuration information, and then obtains related multicast PTM configuration information by monitoring MCCH. In other words, in response to receiving the indication information, the UE releases the PTM configuration corresponding to one of the at least one MBS in response to the wireless communication device switching from the RRC connected state to the RRC inactive state. The UE receives the broadcast signaling for updating the PTM configuration in response to the UE switching from the RRC connected state to the RRC inactive state.

[0152] In some configurations, the RRC release carries an associated SIB message, which includes information required to receive the MCCH. The UE is released to the RRC inactive state, and the UE performs MCCH monitoring based on the information. The SIB indicating the information is carried in the RRC release message. This mechanism reduces the delay in obtaining the associated SIB.

[0153] In some examples, in response to transitioning from an RRC connected state to an RRC inactive state, when the UE is in the RRC inactive state, the UE receives broadcast signaling from the network based on the SIB to obtain a PTM configuration or update the PTM configuration for at least one MBS. The UE receives data corresponding to the at least one MBS from the network based on the update of the PTM configuration.

[0154] In some embodiments, the SIB explicitly indicates that for the selected MBS, in order to continue MBS reception, in response to the UE being released to the RRC inactive state, the corresponding PTM configuration (e.g., the associated MRB and the low-layer configuration of the MBS session) is temporarily retained. The UE initiates a process similar to the MCCH to receive MBS data in the RRC inactive state, for example, by monitoring the MCCH to obtain relevant multicast PTM configuration information. Thus, in response to receiving the SIB, the UE retains the PTM configuration corresponding to one MBS in at least one MBS, so as to continue to receive the one MBS in response to the UE transitioning from the RRC connected state to the RRC inactive state. After the UE receives the PTM configuration through broadcast signaling in the RRC inactive state, the PTM configuration received by the UE in the RRC connected state is released.

[0155] In the absence of receiving such indication information, the UE initiates a conventional RRC connection release procedure and transitions to an RRC inactive state. Before acquiring an updated PTM configuration, the UE continues to apply the current PTM configuration to receive one or more of the at least one MBS, wherein the current PTM configuration may be received when the UE is in an RRC connected state.

[0156] In some embodiments, the SIB explicitly indicates that for the selected MBS, in response to the UE being released to the RRC inactive state, the UE starts a MCCH-like process to receive MBS data in the RRC inactive state, for example, by monitoring the MCCH to obtain relevant PTM configuration information. Thus, in response to receiving the SIB, the UE releases the PTM configuration corresponding to one of the at least one MBS in response to the UE transitioning from the RRC connected state to the RRC inactive state, and the UE receives broadcast signaling from the network for updating to the PTM configuration in response to the UE transitioning from the RRC connected state to the RRC inactive state. In the absence of receiving such indication information, the UE initiates a conventional RRC connection release process and transitions to the RRC inactive state.

[0157] In some configurations, the RRC version carries the MCCH content or the entire MCCH content for the MBS of interest to the UE, which indicates that for such MBS, the corresponding PTM configuration is delivered through a MCCH-like method in the RRC inactive state. This mechanism reduces the delay caused by monitoring the MCCH. The indication information includes broadcast signaling information, which contains the PTM configuration of at least one MBS used when the UE is in the RRC inactive state.

[0158] In one embodiment, in order to continue MBS reception, the UE temporarily retains the corresponding PTM configuration (e.g., the associated MRB and low-layer configuration of the multicast session) in response to the UE being released to the RRC inactive state. The UE applies the PTM configuration in the MCCH content and performs MBS data reception according to the configuration. Then, after the traditional MCCH monitoring process, the UE obtains the MCCH by monitoring the MCCH and notifying the MCCH change by itself. Before obtaining the updated PTM configuration, the UE continues to apply the current PTM configuration to receive one or more of the at least one MBS, wherein the current PTM configuration can be received when the UE is in the RRC connected state.

[0159] In another embodiment, in response to the UE being released to the RRC inactive state, the UE applies the PTM configuration in the MCCH content and performs multicast data reception according to the configuration. Then, after the traditional MCCH monitoring process, the UE obtains the MCCH by monitoring the MCCH and notifying the MCCH change by itself.

[0160] In some embodiments, in response to transitioning from an RRC connected state to an RRC inactive state, the UE receives data corresponding to at least one MBS from the network based on a PTM configuration in the indication information. In response to receiving the indication information, the UE retains the PTM configuration corresponding to one of the at least one MBS to continue receiving the one MBS in response to the UE transitioning from the RRC connected state to the RRC inactive state. In response to receiving the indication information, the UE monitors updates to the PTM configuration in response to the wireless communication device transitioning from the RRC connected state to the RRC inactive state.

[0161] The subject matter described herein sometimes shows the different parts that are contained in different other parts or are connected with different other parts.It should be understood that the architectures of these descriptions are illustrative, and in fact many other architectures that realize the same function can be implemented.In a conceptual sense, any arrangement of the parts realizing the same function is effectively "associated", thereby realizing the desired function.Therefore, any two parts that are combined to realize a specific function here can be regarded as "associated" with each other, so that the desired function is realized, regardless of the architecture or the intermediate parts.Similarly, any two parts that are so associated can also be regarded as "operably connected" or "operably connected" to realize the desired functionality, and any two parts that can be so associated can also be regarded as "operably connectable" to realize the desired functionality.The specific instance that can be operably coupled includes, but is not limited to, physical coordination and / or physical interaction components and / or wireless interaction and / or wireless interaction components and / or logical interaction and / or logical interaction components.

[0162] Regarding the use of plural and / or singular terms herein, those skilled in the art may translate the plural into the singular and / or the singular into the plural as required by the context and / or application. For clarity, various singular / plural arrangements may be explicitly set forth herein.

[0163] Those skilled in the art should understand that, in general, the terms used herein and especially in the appended claims (e.g., the bodies of the appended claims) are generally intended to be “open” terms (e.g., the term “including” should be interpreted as “including but not limited to,” the term “having” should be interpreted as “having at least,” the term “comprising” should be interpreted as “including but not limited to,” etc.).

[0164] Although the drawings and descriptions can illustrate the specific order of method steps, the order of such steps may be different from the order depicted and described, unless specified differently above. In addition, two or more steps can be performed simultaneously or partially simultaneously, unless specified differently above. Such variations can depend on, for example, selected software and hardware systems and on the designer's choice. All these variations are within the scope of the present disclosure. Similarly, the software implementation of the described method can be implemented using standard programming techniques with rule-based logic and other logic to complete different connection steps, processing steps, comparison steps and decision steps.

[0165] It is further understood by those skilled in the art that if a specific number of claims recorded by the introduction is intended, such intention is expressly recorded in the claim, and in the absence of such a record, such intention does not exist. For example, to aid understanding, the following appended claims may include the use of introductory phrases "at least" and "one or more" to introduce claim records. However, the use of such phrases should not be interpreted as implying that the introduction of claim records by the indefinite article "one" or "a kind" will limit any specific claim containing such introduced claim records to the present disclosure containing only one such record, even when the same claim includes the introductory phrases "one or more" or "at least one" and indefinite articles such as "one" or "a kind" (for example, "one" and / or "a kind" should typically be interpreted as meaning "at least one" or "one or more"); the same applies to the use of definite articles to introduce claim records. In addition, even if the specific number of the claim records introduced is expressly recorded, those skilled in the art will recognize that this record should generally be interpreted as meaning at least the number recorded (for example, the record of "two records" without other modifiers generally means at least two records, or two or more records).

[0166] Furthermore, where a convention similar to “at least one of A, B, and C, etc.” is used, generally, such construction is intended to be in the sense that one skilled in the art would understand the convention (e.g., “a system has at least one of A, B, and C” would include but is not limited to systems having A alone, B alone, C alone, A and B together, A and C together, B and C together, and / or A, B, and C together, etc.). Where a convention similar to “at least one of A, B, or C, etc.” is used, generally, such construction is intended to be in the sense that one skilled in the art would understand the convention (e.g., “a system has at least one of A, B, or C” would include but is not limited to systems having A alone, B alone, C alone, A and B together, A and C together, B and C together, and / or A, B, and C together, etc.). One skilled in the art would also understand that almost any disjunctive word and / or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, would be understood to contemplate the possibility of including one, either, or both of these terms. For example, the phrase "A or B" should be understood to include the possibilities of "A" or "B" or "A and B."

[0167] Furthermore, use of the words "approximately," "about," "approximately," "substantially," etc. means ±10% unless otherwise indicated.

[0168] The foregoing description of illustrative implementations has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the precise form disclosed, and modifications and variations are possible in light of the above teachings or may be obtained from practice of the disclosed embodiments. The scope of the present disclosure is intended to be defined by the appended claims and their equivalents.

Claims

1. A wireless communication method, comprising: When the wireless communication device is in a radio resource control (RRC) connected state, the wireless communication device receives a point-to-multipoint (PTM) configuration for each of a plurality of multicast broadcast service (MBSs) from a network using signaling specific to the wireless communication device; The wireless communication device switches from the RRC connected state to the RRC inactive state; In response to transitioning to the RRC inactive state, the wireless communication apparatus receives data of at least one MBS among a plurality of MBSs from a network using the PTM configuration received in the RRC connected state while the wireless communication apparatus is in the RRC inactive state.

2. The method according to claim 1, further comprising: The wireless communication device in the RRC inactive state determines a triggering event; as well as In response to determining the triggering event, the wireless communication device modifies the PTM configuration of the at least one MBS.

3. The method according to claim 1, further comprising: In response to the transition to the RRC inactive state, performing at least one of the following: The wireless communication device reserves the indicated at least one MRB; The wireless communication apparatus stops all running timers except for a multicast discontinuous reception (DRX) timer of the indicated at least one MBS; The wireless communication device clears soft buffers for all downlink hybrid automatic repeat request HARQ processes except for the downlink HARQ process used for the indicated at least one MBS; or The wireless communication device continues to monitor a group radio network temporary identifier (G-RNTI) corresponding to the indicated at least one MBS.

4. The method according to claim 1, wherein: The at least one MBS is a subset of the plurality of MBSs received using a PTM configuration when the wireless communication device is in an RRC connected state.

5. The method according to claim 4, further comprising: The wireless communication apparatus selects the at least one MBS from the plurality of MBSs based on a quality of service (QoS) requirement of each of the plurality of MBSs.

6. The method according to claim 5, wherein: The reserved QoS requirement includes at least one of the following: whether to configure hybrid automatic repeat request HARQ feedback for each of the multiple MBSs; whether an acknowledgement mode AM of a radio link control RLC is configured for at least one MBS radio bearer MRB of each MBS in the plurality of MBSs; or Whether a Packet Data Convergence Protocol (PDCP) status report is configured for at least one MRB of each of the multiple MBSs.

7. The method according to claim 4, further comprising: The wireless communications apparatus receives an indication identifying the at least one MBS from the network, wherein in response to receiving the indication, receiving or continuing to receive the at least one MBS in the RRC inactive state.

8. The method according to claim 7, wherein: The wireless communication device receives the indication through RRC reconfiguration or RRC release; The indication includes an indication for each MBS in the plurality of MBSs, or an indication for each MBS radio bearer MRB associated with the plurality of MBSs.

9. The method according to claim 2, wherein: Determining the triggering event includes receiving, by the wireless communication device, a notification from the network, wherein the wireless communication device receives the notification via a paging message, the paging message including a first part corresponding to an MBS session ID list associated with one of the at least one MBSs and a second part corresponding to modification information associated with the MBS session ID list in the first part.

10. The method according to claim 9, wherein: The modification information indicates that the one MBS among the at least one MBS is suspended; as well as Modifying the PTM configuration includes: When the wireless communication device is in the RRC inactive state, the wireless communication device stops monitoring the one MBS; as well as When the wireless communication device is in the RRC inactive state, the PTM configuration corresponding to the one MBS is suspended.

11. The method according to claim 9, wherein: The modification information indicates restoring the one MBS; as well as Modifying the PTM configuration includes: When the wireless communication device is in the RRC inactive state, the wireless communication device restores the PTM configuration corresponding to the one MBS; as well as When the wireless communication device is in the RRC inactive state, the wireless communication device monitors the one MBS using the PTM configuration.

12. The method according to claim 9, wherein: The modification information indicates that the one MBS among the at least one MBS is inactive; as well as Modifying the PTM configuration includes: When the wireless communication device is in the RRC inactive state, the wireless communication device stops monitoring the one MBS; as well as When the wireless communication device is in the RRC inactive state, the PTM configuration corresponding to the one MBS is released.

13. The method according to claim 9, wherein: The modification information indicates a PTM configuration update of the one MBS among the at least one MBS; as well as Modifying the PTM configuration includes: The wireless communication device initiates the RRC connection recovery process.

14. The method according to claim 13, wherein: In response to initiating the RRC connection recovery procedure, the wireless communication device receives indication information for the one of the at least one MBS from the network, the indication information being the updated PTM configuration and the wireless communication device receives the indication information through RRC release.

15. The method according to claim 13, wherein: In response to initiating the RRC connection recovery process, the wireless communication device receives indication information for the one of the at least one MBS from the network, and the wireless communication device receives the indication information through RRC release to instruct the wireless communication device to obtain the updated PTM configuration from broadcast signaling.

16. The method according to claim 2, wherein: Determining the trigger event includes the wireless communication device receiving a media access control element MACCE from the network when the wireless communication device is in the RRC inactive state, the MAC CE indicating that the PTM configuration for one MBS of the at least one MBS will be modified, wherein modifying the PTM configuration includes one of the following: MBS suspension, MBS resumption, MBS inactivation, or updating the PTM configuration.

17. The method according to claim 2, wherein: Determining the trigger event includes determining, by the wireless communication device, that a reception quality of one of the at least one MBS is below a threshold when the wireless communication device is in the RRC inactive state, wherein the network configures a threshold of at least one of a measured signal strength or a packet loss rate; as well as Modifying the PTM configuration includes: The wireless communication device initiates the RRC connection recovery process; The wireless communication device receives an updated PTM configuration for the one MBS from the network; The wireless communication device receives the one MBS from the network using the updated PTM configuration.

18. The method according to claim 17, wherein: In the RRC connection recovery procedure, the UE indicates a recovery cause value to indicate initiation of the RRC connection recovery procedure to update the PTM configuration of an MBS.

19. A wireless communication device comprising at least a processor and a memory, wherein the at least one processor is configured to read code from the memory and implement the method of claim 1.

20. A computer program product, comprising computer readable program code stored thereon, which, when executed by at least one processor, causes the at least one processor to implement the method of claim 1.

21. A wireless communication method, comprising: When the wireless communication device is in a radio resource control (RRC) connected state, the network sends a point-to-multipoint (PTM) configuration for each of a plurality of multicast broadcast service (MBSs) to the wireless communication device using signaling specific to the wireless communication device; The network releases the wireless communication device to the RRC inactive state; as well as When the wireless communication device is in the RRC inactive state, the network sends data corresponding to at least one MBS among the multiple MBSs to the wireless communication device using the PTM configuration sent when the UE is in the RRC connected state.

22. The method according to claim 21, further comprising: The network sends a threshold value of at least one of a measured signal strength or a packet loss rate to the wireless communication device using signaling specific to the wireless communication device; In response to the RRC connection recovery procedure being initiated if a reception quality of one of the at least one MBS is below a threshold.

23. The method of claim 21, wherein the at least one MBS received when the wireless communication device is in the RRC inactive state is a subset of the plurality of MBSs sent to the wireless communication device using the PTM configuration when the wireless communication device is in the RRC connected state.

24. The method according to claim 23, further comprising: When the wireless communication device is in an RRC idle state, the network determines to send or continue to send the at least one MBS to the wireless communication device; and The network sends an indication identifying the at least one MBS to the wireless communication device.

25. The method according to claim 24, wherein The indication is sent by the network through RRC reconfiguration or RRC release; The indication includes an indication of each MBS in the plurality of MBSs, or an indication of each MBS radio bearer MRB associated with the plurality of MBSs.

26. The method of claim 21, further comprising: The network sends a notification to the wireless communication device, wherein in response to the notification, the wireless communication device modifies the PTM configuration for the at least one MBS.

27. The method according to claim 26, wherein The network sends the notification via a paging message; and The notification includes a first part corresponding to an MBS session ID list associated with one of the at least one MBS and a second part corresponding to modification information associated with the MBS session ID list in the first part.

28. The method of claim 21, further comprising: When the wireless communication device is in the RRC inactive state, the network sends a media access control element MAC CE to the wireless communication device, where the MAC CE indicates that the PTM configuration of one MBS among the at least one MBS is to be modified.

29. A wireless communication device comprising at least a processor and a memory, wherein the at least one processor is configured to read code from the memory and implement the method of claim 21.

30. A computer program product, comprising computer readable program code stored thereon, which, when executed by at least one processor, causes the at least one processor to implement the method of claim 21.

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