Frequency prioritization for terminal devices receiving multicast broadcast services

Abstract

Embodiments of the present disclosure relate to frequency prioritization for terminal devices receiving multicast broadcast services. According to one aspect, there is provided an apparatus configured to perform the following. The apparatus receives a service advertisement for a multicast broadcast service. The apparatus receives at least one indication in the service announcement, and / or in at least one message after the service announcement, the at least one indication specifying a terminal device supporting all or at least some reduced capabilities for multicast broadcast services. The apparatus performs a cell reselection procedure based on the cell measurement and the at least one indication.

Description

Technical Field

[0001] Various example embodiments relate to wireless communications. Background Art

[0002] Reduced Capability (RedCap) terminal devices are terminal devices that comply with certain predefined bandwidth (BW) restrictions. In other words, RedCap terminal devices cannot adopt a reception bandwidth greater than a predefined maximum bandwidth (e.g., 20MHz). Correspondingly, RedCap-specific Common Frequency Resources (CFRs) have been introduced for receiving multicast broadcast services (MBS) by RedCap terminal devices. Since the service area of ​​a specific temporary mobile group identity (TMGI) may include both access nodes that support and do not support RedCap CFRs, the same frequency selection guidance for cell reselection is not applicable to both RedCap and non-RedCap terminal devices, due to the fact that RedCap terminal devices can only receive services in some of the cells in the service area. Therefore, a new mechanism is needed to guide both RedCap and non-RedCap terminal devices to make cell reselection decisions in different ways. Summary of the invention

[0003] According to one aspect, the subject matter of the independent claims is provided. Embodiments are defined in the dependent claims.

[0004] One or more examples of implementations are set forth in more detail in the drawings and the description that follows. Other features will be apparent from the description and drawings, and from the claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0005] Figure 1 illustrates a system to which some embodiments may be applied;

[0006] Figures 2 to 4 illustrates a process according to an embodiment;

[0007] Figure 5 illustrates a signaling scenario between a terminal device, three access nodes, and a core network according to an embodiment;

[0008] Fig. 6A and Figure 6B illustrates two exemplary signaling scenarios between a terminal device, three access nodes, and a core network for performing cell reselection according to an embodiment;

[0009] Figure 7 and Figure 8illustrates two alternative core network signaling scenarios between a multicast / broadcast session management function (MB-SMF), a network exposure function (NEF), and an application function (AF) for enabling cell reselection according to an embodiment;

[0010] Figures 9 to 11 illustrates a process according to an embodiment;

[0011] Fig.12 illustrates a signaling scenario between a terminal device, three access nodes, and a core network according to an embodiment; and

[0012] Fig.13 An apparatus according to some embodiments is illustrated. DETAILED DESCRIPTION

[0013] The following embodiments are presented as examples only. Although this specification may refer to "one", "an" or "some" embodiments and / or examples in several places in the text, this does not necessarily mean that each reference refers to the same (multiple) embodiments or (multiple) examples, or that a particular feature applies only to a single embodiment and / or example. Individual features of different embodiments and / or examples may also be combined to provide other embodiments and / or examples.

[0014] As used herein, “at least one of: ” and “at least one of ” and similar expressions (wherein a list of two or more elements is connected by “and” or “or”) mean at least any one of the elements, or at least any two or more of the elements, or at least all of the elements.

[0015] As used herein, equivalent terms "Reduced Capability Terminal Device", "RedCap Terminal Device", "Reduced Capability User Equipment" and "RedCap UE" may be defined as follows. The 3rd Generation Partnership Project (3GPP) has introduced Reduced Capability (RedCap) devices in New Radio (NR) Release 17 (Rel-17). For example, a RedCap device may also be referred to as a RedCap terminal device, RedCap UE, NR-Lite device or NR-Light device. The 3GPP RedCap NR feature reduces UE complexity through fewer receiver / transmitter (Rx / Tx) antennas, reduced UE bandwidth usage, lower UE power consumption, relaxed data rates, relaxed UE processing time and processing power to help enable some exciting use cases, such as around industrial wireless sensors, video surveillance and wearable devices.

[0016] In NR, the frequency range below 6 GHz or 7 GHz may be referred to as FR1, and the frequency range above 24 GHz (or more precisely, 24 to 52.6 GHz) may be referred to as FR2. During and after initial access, the maximum bandwidth of a FR1 RedCap UE is 20 MHz. During and after initial access, the maximum bandwidth of a FR2 RedCap UE is 100 MHz. For frequency bands that require a legacy NR UE to be equipped with a minimum of 2 receive (Rx) antenna ports, or with a minimum of 4 Rx antenna ports, the minimum number of Rx branches supported for a RedCap UE is 1. For a RedCap UE with 1 Rx branch, 1 downlink (DL) multiple-input multiple-output (MIMO) layer is supported. For a RedCap UE with 2 Rx branches, 2 DL MIMO layers are supported.

[0017] RedCap devices may co-exist with non-RedCap UEs (ie, in a given cell, both RedCap devices and non-RedCap UEs may exist).

[0018] In the following, a radio access architecture based on Long Term Evolution Advanced (LTE-Advanced, LTE-A) or New Radio (NR, 5G) will be used as an example of an access architecture to which the embodiments may be applied to describe different exemplary embodiments, however, the embodiments are not limited to such an architecture. It is obvious to a person skilled in the art that these embodiments may also be applied to other types of communication networks with suitable components by appropriately adjusting the parameters and processes. Some examples of other options for suitable systems are Universal Mobile Telecommunications System (UMTS) Radio Access Network (UTRAN or E-UTRAN), Long Term Evolution (LTE, same as E-UTRA), Wireless Local Area Network (WLAN or WiFi), Worldwide Interoperability for Microwave Access (WiMAX), Personal Communications Service (PCS), Wideband Code Division Multiple Access (WCDMA), systems using Ultra-Wideband (UWB) technology, sensor networks, mobile ad hoc networks (MANETs), and Internet Protocol Multimedia Subsystem (IMS), or any combination thereof.

[0019] Figure 1 An example of a simplified system architecture is depicted showing only some elements and functional entities (all of which are logical units, the implementation of which may differ from what is shown). Figure 1 The connections shown in the figure are logical connections; the actual physical connections may be different. It will be apparent to those skilled in the art that the system typically also includes Figure 1 Other functions and structures than those shown in .

[0020] However, the embodiments are not limited to the systems given as examples, but those skilled in the art may apply the technical solution to other communication systems having the necessary properties.

[0021] Figure 1 The example of FIG. 1 shows a portion of an exemplary radio access network.

[0022] The communication system usually includes more than one (e / g)NodeB, in which case, the (e / g)NodeB can also be configured to communicate with each other through a wired or wireless link designed for this purpose. These links can be used for signaling purposes. (e / g)NodeB is a computing device configured to control the radio resources of the communication system to which it is coupled. NodeB can also be referred to as a base station, an access point, or any other type of docking device, including a relay station capable of operating in a wireless environment. (e / g)NodeB includes, or is coupled to, a transceiver. A connection to an antenna unit is provided from the transceiver of the (e / g)NodeB, and the antenna unit establishes a bidirectional radio link to a user equipment. The antenna unit may include multiple antennas or antenna elements. (e / g)NodeB is also connected to a core network 110 (CN or next generation core NGC). Depending on the system, the counterpart on the CN side may be a serving gateway (S-GW, routing and forwarding user data packets), a packet data network gateway (P-GW) for providing connectivity of a user equipment (UE) to an external packet data network, or a mobile management entity (MME), etc.

[0023] In some embodiments, the core network 110 may include an application function (AF). The AF is a functional element that provides service or application related information to network function (NF) service consumers. The AF may provide one or more services. The AF resides in the control plane of the 5G service-based architecture (SBA). For example, the responsibilities of the AF include accessing the network exposure function (NEF) to retrieve resources, interacting with the policy control function (PCF) to enable policy control, performing service routing for applications, and providing application services to subscribers.

[0024] In some embodiments, the core network 110 may include a network exposure function (NEF). For example, the NEF may be configured to securely expose services and capabilities provided by 3GPP network functions.

[0025] In some embodiments, the core network 110 may include a multicast / broadcast session management function (MB-SMF). For example, the MBS-SMF may be configured to manage a multicast / broadcast service (MBS) session, and interact with the RAN and a multicast / broadcast user plane function (MB-UPF) for data transmission. It should be noted that the term "multicast / broadcast" is equivalent to the alternative terms "multicast-broadcast" or "multicast broadcast" used throughout the relevant technical field.

[0026] A user equipment (also referred to as UE, user device, user terminal, terminal device, etc.) illustrates a type of apparatus to which resources on the air interface are allocated and assigned, and therefore any features described herein using a user equipment may be implemented using a corresponding apparatus (such as a relay node). An example of such a relay node is a layer 3 relay (self-backhaul relay) toward a base station. A user equipment may include a mobile device, and at least one universal integrated circuit card (UICC).

[0027] User equipment generally refers to a portable computing device, which includes wireless mobile communication devices operating with or without a subscriber identity module (SIM) or UICC, including but not limited to the following types of devices: mobile stations (mobile phones), smart phones, personal digital assistants (PDAs), mobile phones, devices using wireless modems (alarms or measuring devices, etc.), laptop computers and / or touch screen computers, tablet computers, game consoles, notebooks, and multimedia devices. It should be understood that user equipment can also be almost exclusively uplink-only devices, an example of which is a camera or video camera that loads images or video clips to a network. User equipment can also be a device with the ability to operate in an Internet of Things (IoT) network, which is a scenario in which objects are provided with the ability to transmit data over a network without human-to-human or human-to-computer interaction. User equipment (or in some embodiments, a layer 3 relay node) is configured to perform one or more user equipment functions in the user equipment function. User equipment can also be referred to as a subscriber unit, a mobile station, a remote terminal, an access terminal, a user terminal, or a user equipment (UE), just to name a few names or devices.

[0028] The various techniques described herein may also be applied to cyber-physical systems (CPS) (systems of cooperating computing elements that control physical entities). CPS may enable the implementation and utilization of a large number of interconnected ICT devices (sensors, actuators, processors microcontrollers, etc.) embedded in physical objects at different locations. Mobile cyber-physical systems are a subcategory of cyber-physical systems where the physical systems in question have inherent mobility. Examples of mobile physical systems include mobile robots, and electronic devices transported by humans or animals.

[0029] It should be understood that Figure 1 In the figure, for the sake of clarity only, the user equipment is depicted as including 2 antennas. The number of receiving and / or transmitting antennas may naturally vary according to the current implementation.

[0030] Furthermore, although the apparatus is depicted as a single entity, different units, processors and / or memory units ( Figure 1 Not all are shown) can be implemented.

[0031] 5G enables the use of multiple-input multiple-output (MIMO) antennas, many more base stations or nodes than LTE (the so-called small cell concept), including macro sites that operate in cooperation with smaller stations, and adopts various radio technologies according to service requirements, use cases and / or available spectrum. 5G mobile communications support a wide range of use cases and related applications, including video streaming, augmented reality, different data sharing methods, and various forms of machine-type applications, including vehicle safety, different sensors, and real-time control. 5G is expected to have multiple radio interfaces, namely below 6GHz, centimeter waves, and millimeter waves, and can also be integrated with existing traditional radio access technologies (such as LTE). At least in the early stages, integration with LTE can be achieved as a system, where macro coverage is provided by LTE, and 5G radio interface access comes from small cells aggregated to LTE. In other words, 5G is planned to support both inter-RAT operability (such as LTE-5G) and inter-RI operability (inter-radio interface operability, such as below 6GHz-centimeter wave, below 6GHz-centimeter wave-millimeter wave). One of the concepts being considered for use in 5G networks is network slicing, where multiple independent and dedicated virtual subnetworks (network instances) can be created within the same infrastructure to run services with different requirements for latency, reliability, throughput, and mobility.

[0032] The current architecture in LTE networks is fully distributed in the radio and fully centralized in the core network. Low-latency applications and services in 5G require bringing content close to the radio, which leads to local breakthroughs and multi-access edge computing (MEC). 5G enables analysis and knowledge generation at the data source. This approach requires the use of resources that may not be continuously connected to the network, such as laptops, smartphones, tablets, and sensors. MEC provides a distributed computing environment for application and service hosting. It also has the ability to store and process content close to cellular subscribers for faster response times. Edge computing covers a wide range of technologies such as wireless sensor networks, mobile data collection, mobile signature analysis, collaborative distributed peer-to-peer self-organizing networks and processing, and can also be classified as local cloud / fog computing and grid / mesh computing, dew computing, mobile edge computing, cloud, distributed data storage and retrieval, autonomous self-healing networks, remote cloud services, augmented and virtual reality, data caching, Internet of Things (massive connectivity and / or latency critical), critical communications (autonomous vehicles, traffic safety, real-time analysis, time-critical control, health care applications).

[0033] The communication system may also be able to communicate with or utilize services provided by other networks, such as the public switched telephone network or the Internet 112. The communication network may also be able to support the use of cloud services, for example, at least part of the core network operations may be performed as a cloud service (this is in the Figure 1 114). The communication system may also include a central control entity or the like providing facilities for the networks of different operators to collaborate, for example in terms of spectrum sharing.

[0034] Edge cloud can be introduced into RAN by utilizing network function virtualization (NVF) and software defined network (SDN). Using edge cloud can mean that access node operation is performed at least partially in a server, host or node, which is operatively coupled to a remote radio head or unit (RU), or a base station including a radio part. It is also possible that the node operation will be distributed among multiple servers, nodes or hosts. The application of cloudRAN architecture enables RAN real-time functions to be performed at the RAN side (in the distributed unit DU 104), and non-real-time functions to be performed in a centralized manner (in the central or centralized unit CU 108). Therefore, in summary, RAN can include at least one distributed access node, which includes a central unit, one or more distributed units communicatively connected to the central unit, and one or more (remote) radio heads or units, each of which is communicatively connected to at least one of the one or more distributed units.

[0035] It should also be understood that the distribution of labor between core network operations and base station operations may be different from that of LTE, or even non-existent. Some other technological advances that may be used are big data and all-IP, which may change the way networks are being built and managed. 5G (or New Radio, NR) networks are being designed to support multiple hierarchical structures, where MEC servers can be placed between the core and the base station or nodeB (gNB). It should be recognized that MEC can also be applied in 4G networks.

[0036] 5G can also make use of satellite communications to enhance or supplement the coverage of 5G services, for example by providing backhaul. Possible use cases are to provide service continuity to machine-to-machine (M2M) or Internet of Things (IoT) devices or on-board passengers, or to ensure service availability for critical communications, as well as future railway / maritime / aeronautical communications. Satellite communications can make use of geostationary orbit (GEO) satellite systems, but also low earth orbit (LEO) satellite systems, in particular mega constellations (systems in which hundreds of (nano) satellites are deployed). Each satellite 106 in a mega constellation can cover several satellite-enabled network entities that create a ground cell. The ground cell can be created by a ground relay node 104, or by a gNB located on the ground or in a satellite.

[0037] It is obvious to a person skilled in the art that the depicted system is only an example of a part of a radio access system, and in practice the system may include multiple (e / g)NodeBs, a user equipment may be able to access multiple radio cells, and the system may also include other devices, such as physical layer relay nodes or other network elements. At least one of the (e / g)NodeBs may be a home (e / g)nodeB. Furthermore, in a geographical area of ​​the radio communication system, a plurality of different kinds of radio cells, as well as a plurality of radio cells, may be provided. A radio cell may be a macro cell (or umbrella cell), which is a large cell typically having a diameter of up to tens of kilometers, or a smaller cell, such as a micro cell, a femto cell, or a pico cell. Figure 1 The (e / g)NodeB can provide any kind of these cells. A cellular radio system can be implemented as a multi-layer network including several kinds of cells. Usually, in a multi-layer network, one access node provides one cell or multiple cells of one type, and therefore multiple (e / g)NodeBs are required to provide such a network structure.

[0038] In order to meet the needs of improving the deployment and performance of communication systems, the concept of "plug and play" (e / g) NodeB has been introduced. Generally, a network that can use "plug and play" (e / g) NodeB includes, in addition to the home (e / g) NodeB (H(e / g)nodeB), a home NodeB gateway or HNB-GW ( Figure 1 The HNB gateway (HNB-GW) usually installed in the operator's network can aggregate services from a large number of HNBs back to the core network.

[0039] The 6G architecture is designed to enable easy integration of everything, such as networks, joint communications and sensing, non-terrestrial networks and terrestrial communications. It is envisioned that 6G systems contain machine learning algorithms and local and distributed computing capabilities, where virtualized network functions can be distributed on core and edge computing resources. Far edge computing, where computing resources are pushed to the very edge of the network, will become part of a distributed computing environment, for example in a "zero latency" scenario. 5G systems can also adopt this capability. More generally, it is envisioned that the actual (radio) communication system consists of one or more computer programs executed within a programmable infrastructure such as a general-purpose computing entity (server, processor, etc.).

[0040] At least some of the embodiments to be discussed below specifically relate to broadcast as defined in Release 17 of the Third Generation Partnership Project (3GPP). Among them, broadcast services are defined as an alternative to multicast services. In a broadcast service, one transmitter sends services to all users (or UEs) in a broadcast service area. In a multicast service, one or more transmitters send services to a group of dedicated users (or UEs). As long as the UE is within coverage, the broadcast service enables the UE to receive in any radio resource control (RRC) state. Unlike in a multicast service, specific service announcements related to the MBS broadcast service and the public land mobile network (PLMN) need to be used in a broadcast service. A temporary mobile group identity (TMGI) is supported as an identifier for an MBS broadcast session.

[0041] UEs in any RRC state may be able to receive broadcast services. Configuration of MBS broadcast services is provided via System Information Block 20 (SIB20) / Multicast Control Channel (MCCH) transmitted periodically in each cell within the MBS service area. UEs may receive MCCH and the broadcast data itself in a frequency region known as Common Frequency Resources (CFR).

[0042] For broadcast, the UE receives a frequency selection area identifier (FSAI) or an identifier (of a broadcast MBS session) applicable to the MBS service via a service announcement for the MBS service (which may be sent via unicast or using another broadcast session). Generally, the (MBS) FSAI is used for broadcast MBS sessions to guide the frequency selection of the UE. The FSAI is sometimes also referred to as an FSA identifier (FSA ID). Specifically, the (MBS) FSAI identifies a preconfigured area within and near which (multiple) cells announce the MBS FSAI and associated frequencies. The same (multiple) FSAI may be applicable to multiple MBS services and / or multiple broadcast MBS sessions.

[0043] A RAN node (e.g., an access node) may be configured with a FSAI. For example, the configuration of the FSAI may be performed via an operation, administration, and maintenance (OAM) entity. The RAN node may exchange this information with a neighboring RAN node. This information may be exchanged via an Xn interface. Based on the configuration of the FSAI, the RAN node may announce information about the configured MBS FSAI and the operating frequency of the RAN node in the SIB over the radio interface. That is, in the system information block 21 (SIB21) of the cell, the UE is able to see the mapping of the FSAI to the neighboring cell frequency (i.e., the frequency used by the neighboring RAN node of the UE's serving node). The UE may then prioritize the neighboring cell frequency in frequency selection based on the exchanged information. For example, a UE in an RRC idle or inactive state may prioritize camping on the frequency of a cell that provides a specific broadcast session that the UE is interested in receiving. The UE may compare the (multiple) MBS FSAI included in the service announcement with the (multiple) MBS FSAI included in the (multiple) SIB to perform frequency selection. It should be noted that the UE may also or alternatively receive the frequency providing the service directly in the service announcement. In this case, the UE may directly prioritize the frequencies indicated in the service announcement. Therefore, the UE may not necessarily need (multiple) FSAI or SIB21 to perform frequency selection.

[0044] When a broadcast MBS session is created, the AF may provide (multiple) MBS FSAI based on the (service) agreement. If the AF does not provide (multiple) MBS FSAI, the MB-SMF may determine (multiple) MBS FSAI based on a preconfigured mapping from the MBS service area and / or broadcast MBS session information (e.g., application ID) to (multiple) MBS FSAI, and send the determined (multiple) MBS FSAI to the AF (optionally, via the NEF).

[0045] In some cases, during a broadcast MBS session start, and during a broadcast MBS session update, the MB-SMF may include the MBS FSAI(s) for the MBS session and send them to the RAN node via the Application Management Function (AMF). The RAN node may then use these MBS FSAI(s) to determine the cells and / or frequencies within the MBS service area to broadcast the MBS session data.

[0046] In the following, reduced capability UEs or terminal devices will be discussed in further detail to provide context and background for the embodiments. Reduced capability (RedCap) terminal devices are terminal devices with certain predefined bandwidth (BW) restrictions. That is, RedCap terminal devices cannot adopt a reception bandwidth greater than a predefined maximum bandwidth (e.g., 20MHz). If the initial bandwidth part (BWP) of the system is greater than such restrictions, the RedCap terminal device utilizes an initial BWP configured separately, for example, by system information block 1 (SIB1). If the CFR of MBS is properly configured for the RedCap terminal device, the RedCap terminal device may be able to receive broadcast data. That is, broadcast data may be received as long as the CFR bandwidth is less than or equal to the supported bandwidth of the RedCap terminal device. Services (e.g., MBS) can be delivered in a dedicated RedCap CFR. Which CFR should be utilized for a specific service depends on the access node (e.g., gNB) because there is no indication from the core network to the access node that a broadcast session is received by a non-RedCap / RedCap terminal device.

[0047] As described above, a new RedCap MBS CFR different from the earlier broadcast MBS CFR has been introduced for receiving broadcast control and data. It is assumed that some services will be sent in the RedCap CFR, and how the gNB chooses whether to utilize such CFR is determined by OAM configuration.

[0048] Non-RedCap terminal devices are not expected to read the RedCap CFR, and RedCap terminal devices are unable to read the non-RedCap CFR due to capability limitations. Therefore, if the broadcast service is for both RedCap and non-RedCap terminal devices, the access node should send the same service in two different CFRs. Therefore, separate SIB20 and MCCH are used for RedCap terminal devices. If there are one or more access nodes in the service area of ​​a particular TMGI that do not utilize a separate RedCap CFR (for example, because the access node is not configured for the function, or simply decides to send services only in the non-RedCap CFR due to, for example, congestion), the same frequency selection guidance does not apply to both RedCap and non-RedCap terminal devices. That is, if the same frequency selection guidance based on a separate RedCap CFR would be used, the RedCap terminal device would only be able to receive services in some of the cells in the service area.

[0049] Therefore, a new mechanism is needed to differently guide RedCap and non-RedCap terminal devices receiving broadcast services (eg, MBS) to make cell reselection decisions. The embodiments to be discussed below are used to provide such a mechanism.

[0050] Figure 2 A process for performing an informed cell reselection decision according to an embodiment is illustrated. Figure 2 The illustrated process may be performed by a terminal device (or UE) or a part thereof. Here, the terminal device may be Figure 1 The terminal device may be a RedCap terminal device or a non-RedCap terminal device. In the following, for simplicity, the execution Figure 2 The entities of a process are called devices.

[0051] refer to Figure 2 The apparatus receives a service announcement of an MBS in block 201. The service announcement received in block 201 may correspond to a broadcast transmission. The service announcement may be sent (or broadcast) by an access node (e.g., a gNB). The service announcement may be initiated by an AF.

[0052] The service announcement of box 201 includes at least one of the following items: 1) at least one FSAI and at least one indication indicating that the at least one FSAI is defined for RedCap terminal devices; or 2) at least one frequency and at least one indication indicating that the at least one frequency is defined for RedCap terminal devices. At least one FSAI and / or at least one frequency are associated with the MBS indicated in the service announcement. In other words, a new indication for at least one FSAI or at least one frequency (or both) is included in the service announcement to indicate that the at least one FSAI or frequency is specifically used to guide RedCap terminal devices to neighboring cell frequencies, which can be used to provide MBS according to the BWP restrictions of RedCap UEs. Based on at least one indication (of any of the above types), the receiving device is able to distinguish between optimized FSAI / frequencies for RedCap and non-RedCap.

[0053] In some alternative embodiments, at least one of the (new) indications discussed in the previous paragraph may be received in a message other than a service announcement.

[0054] In some embodiments, the service announcement of block 201 may also include at least one FSAI or at least one frequency without any indication that the at least one FSAI or the at least one frequency will be defined for RedCap terminal devices. In other words, the at least one additional FSAI or frequency may not be associated with any indication that the at least one additional FSAI / frequency is defined for RedCap terminal devices. However, it should be emphasized that even if the at least one additional FSAI / frequency is not specifically adapted for use with RedCap terminal devices, in some cases they may still be usable with at least some RedCap terminal devices.

[0055] In some embodiments, for at least one of at least one FSAI or at least one frequency defined for a RedCap terminal device, the service announcement may also include: information about at least one bandwidth restriction condition, which is indicated as the at least one FSAI or at least one frequency defined for a terminal device with reduced capabilities that complies with the at least one bandwidth restriction condition. For example, at least one bandwidth restriction condition may include: at least one condition specifying a restriction in terms of terminal device type (e.g., only supporting UE type 1), and / or at least one condition specifying a restriction in terms of bandwidth or bandwidth portion (e.g., 100MHz bandwidth restriction). Here, it is assumed that the terminal device type is associated with (multiple) bandwidths or (multiple) frequency bands that can be used by terminal devices of the defined type. For example, each terminal device type is associated with at least one bandwidth or at least one frequency band. The terminal device may store in a memory information about a mapping between one or more terminal device types and a list of one or more associated bandwidths and / or frequency bands. The at least one FSAI and / or at least one frequency can be adopted by the terminal device only when the terminal device satisfies or is compatible with at least one bandwidth restriction condition.

[0056] When an apparatus (eg, terminal device) receives a service announcement for an MBS in block 201, the apparatus may be in any RRC state. After receiving the service announcement for the MBS, the apparatus may transition to an RRC inactive or idle state and start receiving the MBS specified by the service announcement.

[0057] Subsequently, the device performs a cell reselection process based on cell measurement and service announcement in block 202. Specifically, in addition to cell measurement, the cell reselection process may also use the at least one FSAI and the associated at least one indication (option 1); or the at least one frequency and the associated at least one indication (option 2).

[0058] The cell measurements may be performed by the device itself. The cell measurements may include measurements of signals sent by one or more access nodes. The cell measurements may include measurements of, for example, at least one of the following items: reference signal received power (RSRP), reference signal receiver quality (RSRQ), signal to noise ratio (SNR), or signal to interference plus noise ratio (SINR). The cell measurements may include measurements of one or more (radio) frequencies involved (used in one or more neighboring cells). The cell measurements may include any cell measurements performed in an RRC inactive or idle state, as defined in 3GPP TS 38.306 and / or TS 38.304.

[0059] How the service announcement is used in the cell reselection process depends on whether the apparatus is a RedCap terminal device (or a portion thereof) or a non-RedCap terminal device (or a portion thereof).

[0060] If the apparatus is a RedCap terminal device (or part thereof), performing a cell reselection process based on the service announcement in box 202 may include: giving priority to frequencies associated with at least one FSAI or at least one frequency defined for RedCap terminal devices during the cell reselection process. Here and in the following discussion related to box 202, the frequencies given priority may specifically refer to neighboring cell frequencies (i.e., frequencies used in one or more neighboring cells of the terminal device). Neighboring cell frequencies are operating frequencies of neighboring cells of the serving cell of the apparatus. If the service announcement of box 201 includes the above-mentioned one or more FSAIs or frequencies that are not indicated as defined for RedCap terminal devices, the apparatus may specifically give priority to frequencies associated with at least one FSAI or at least one frequency that are indicated as defined for RedCap terminal devices during the cell reselection process, at least relative to frequencies associated with one or more FSAIs or one or more frequencies that are not indicated as defined for RedCap terminal devices. Optionally, if one or more FSAIs or frequencies for RedCap terminal devices are not available in the current cell of the device (e.g., because SIB21 does not contain a corresponding FSAI to neighboring cell mapping), the device may prioritize one or more FSAIs or frequencies not defined for RedCap terminal devices over at least one FSAI or frequency defined for RedCap terminal devices. If the limitations of the device allow it to receive non-RedCap CFRs, the device may still be able to receive MBS in non-RedCap CFRs.

[0061] If the apparatus is a non-RedCap terminal device (or a portion thereof), performing a cell reselection process based on a service announcement in block 202 may include avoiding or ignoring, during the cell reselection process, frequencies associated with at least one FSAI or at least one frequency indicated as defined for a RedCap terminal device.

[0062] If the apparatus is a non-RedCap terminal device (or a portion thereof), and the service announcement of box 201 also includes the above-mentioned one or more FSAIs or frequencies that are not indicated as defined for RedCap terminal devices, then performing a cell reselection process based on the service announcement in box 202 may include: in the cell reselection process, giving priority to frequencies associated with one or more FSAIs or one or more frequencies that are not indicated as defined for RedCap terminal devices relative to frequencies associated with at least one FSAI or at least one frequency that are indicated as defined for RedCap terminal devices. Optionally, if one or more FSAIs or frequencies for non-RedCap terminal devices are not available in the current cell of the apparatus (for example, because SIB21 does not contain a corresponding FSAI to neighboring cell mapping), the apparatus may give priority to at least one FSAI or frequency defined for RedCap terminal devices relative to one or more FSAIs or frequencies defined for non-RedCap terminal devices. For example, this may be useful in a scenario where services are only provided in RedCap CFR (and ordinary terminal devices are directed to RedCap CFR).

[0063] If the apparatus is a RedCap terminal device, and the service announcement of block 201 includes information about at least one bandwidth restriction condition that is indicated to be satisfied by at least one FSAI or at least one frequency defined for the RedCap terminal device, the apparatus may perform the following operations. First, for at least one frequency or at least one FSAI associated with at least one bandwidth restriction condition, the apparatus may determine whether the RedCap terminal device satisfies at least one bandwidth restriction condition. Subsequently, during the cell reselection process, the apparatus may give priority to frequencies associated with at least one FSAI or at least one frequency for which the RedCap terminal device satisfies at least one bandwidth restriction condition.

[0064] In some more general embodiments, the device may receive a service announcement for an MBS and receive in the service announcement, or in at least one message after the service announcement (or in both), at least one indication indicating support of neighboring cells for all or at least some RedCap terminal devices for the MBS (or MBS session). The at least some RedCap terminal devices may correspond to, for example, RedCap terminal devices that satisfy at least one UE type or bandwidth restriction condition. The at least one message after the service announcement may include, for example, at least one SIB21 message. Subsequently, the device may perform a cell reselection procedure based on cell measurements and at least one indication (and optionally, also based on the service announcement), similar to as described in box 201).

[0065] Figure 3A process for performing an informed cell reselection decision according to an embodiment is illustrated. Figure 3 The process shown in can be performed by a terminal device (or UE) or a part thereof. Here, the terminal device can be Figure 1 The terminal device may be a RedCap terminal device or a non-RedCap terminal device. In the following, for simplicity, the execution Figure 3 The entities of a process are called devices.

[0066] Figure 3 The process corresponds largely to Figure 2 process. Figure 2 Any characteristics and definitions provided shall apply to Figure 3 process, but with some flexibility.

[0067] refer to Figure 3 In block 301, an apparatus receives a service announcement for an MBS. The service announcement received in block 301 may correspond to a broadcast transmission. The service announcement may be sent by an access node (e.g., a gNB). The service announcement may be initiated by an AF.

[0068] The service announcement of block 301 includes at least: at least one frequency, and at least one indication indicating that the at least one frequency is defined for a RedCap terminal device (i.e., the service announcement corresponds to option 2 discussed in conjunction with block 201). The at least one frequency may include (or consist of) at least one neighboring cell frequency of the device (i.e., at least one frequency of a neighboring cell of a serving cell of the device). The at least one frequency is associated with an MBS indicated in the service announcement. If a frequency associated with an MBS is already given in the service announcement, the UE may directly prioritize the frequency.

[0069] The service announcement may include at least one FSAI and at least one indication indicating that the at least one FSAI is defined for a RedCap terminal device. The service announcement may include at least one frequency or at least one FSAI and at least one indication indicating that the at least one frequency or at least one FSAI is defined for a RedCap terminal device.

[0070] After receiving the service announcement of the MBS, in block 302, the device receives at least one FSAI to frequency mapping including the at least one frequency. Thus, based on the at least one FSAI to frequency mapping, the device is able to determine at least one FSAI corresponding to the at least one frequency. The at least one FSAI to frequency mapping may be received from the access node. The at least one FSAI to frequency mapping may form part of a broadcast transmission of the access node. The reception in block 302 may include, for example, receiving a SIB21 broadcast including the at least one FSAI to frequency mapping including the at least one frequency. In block 302, during the reception of the at least one FSAI to frequency mapping, the device may be in any RRC state. The device may transition to an RRC inactive or idle state and begin receiving the MBS specified in the service announcement.

[0071] Subsequently, in block 303, the apparatus performs a cell reselection procedure based on the cell measurement, the service announcement, and the at least one FSAI to frequency mapping. Specifically, in addition to the cell measurement and the at least one FSAI to frequency mapping, the cell reselection procedure may also use the at least one (neighboring cell) frequency included in the service announcement, and the associated at least one indication. In addition to performing the cell reselection procedure using the at least one FSAI to frequency mapping, the execution of the cell selection procedure may also be combined with Figure 2 The process is performed as described in block 202 of FIG.

[0072] Figure 4 A process for enabling an informed cell reselection decision according to an embodiment is illustrated. Figure 4 The process shown in can be performed by an application function (AF) or a part thereof. Here, AF can be included in Figure 1 In the core network 110. Figure 4 Dashed lines are used to indicate optional features. In the following, for simplicity, the execution Figure 4 The entities of a process are called devices.

[0073] See also Figure 4In box 401, the device sends a service announcement of MBS to at least one terminal device via at least one access node (and optionally one or more core network nodes). Here, the service announcement includes (similar to as described in conjunction with the above embodiments) at least one FSAI, and at least one indication indicating that the at least one FSAI is defined for a RedCap terminal device; or at least one frequency defined for a terminal device with reduced capabilities, and at least one indication indicating that the at least one frequency is defined for a RedCap terminal device. The at least one frequency may include (or consist of) one or more neighboring cell frequencies of the device. The service announcement may be defined as described in conjunction with the above embodiments. At least one access node may only broadcast / send the service announcement without accessing its content.

[0074] In box 402, the device causes or triggers the transmission of a broadcast MBS session establishment request by the MB-SMF to at least one access node. The causing or triggering may include: sending an MBS session creation (or creation) request for the MBS session to the MB-SMF via the NEF. The MBS session creation (or creation) request may include: at least one FSAI, and at least one indication indicating that the at least one FSAI is defined for a RedCap terminal device. Upon receiving the MBS session creation request, the MB-SMF may use at least one indication indicating that the at least one FSAI is used to send the broadcast MBS session establishment request. In combination Figure 7 This feature is described in further detail.

[0075] In some embodiments, block 402 may be omitted. That is, in such embodiments, the transmission of the broadcast MBS session establishment request may still be performed, but not (directly) triggered by the device (e.g., AF), but by the MB-SMF itself when generating at least one FSAI for a RedCap terminal device. In these embodiments, the device may still send an MBS session creation (or creation) request for an MBS session, but without including at least one FSAI and at least one associated indication indicating that the at least one FSAI is defined for a RedCap terminal device. In combination Figure 8 This feature is described in further detail.

[0076] Figure 5 The diagram shows the signaling between a RedCap terminal device (hereinafter, for simplicity, referred to as a terminal device), a first access node, a second access node, a third access node, and a core network. The first access node, the second access node, and the third access node (for example, a gNB) can use corresponding (carrier) frequencies f 1 、f 2 and f 3, and corresponding FSAIs (FSAI2, FSAI2 and FSAI1) to provide services for cells 1, 2 and 3. Here, FSAI2 may be a FSAI defined for RedCap terminal devices, and FSAI1 may be a FSAI not specifically defined for RedCap terminal devices. The terminal device may operate in cell 1. Functions associated with the core network may be performed by the application function (AF) of the core network communicating with the network exposure function (NEF) of the core network and the multicast / broadcast session management function (MB-SMF) of the core network. Although Figure 5 The diagram shows a communication scenario in which the first access node providing the (initial) service cell for the terminal device has two adjacent access nodes. Figure 5 The described features and functionalities may also be equally applicable to the case where the first access node has a single neighboring access node, or has more than two neighboring access nodes.

[0077] refer to Figure 5 , as an initial pre-configuration step, in box 501, the access node obtains or receives configuration information from an OAM entity. The OAM entity (or multiple entities) may be located in the core network. The configuration information includes at least one indication indicating that the at least one FSAI is defined for a terminal device with reduced capabilities. Here, the at least one FSAI includes at least FSAI2. In other words, in this example, the OAM entity (or multiple entities) configures FSAI2 marked as for RedCap terminal devices. In some embodiments, box 501 may be omitted (i.e., the associated features may be considered optional).

[0078] In some embodiments, the configuration information of block 501 may also define the bandwidth of the CFR defined for reduced capability terminal devices.

[0079] In some embodiments, the configuration information of block 501 may optionally further include a mapping between the FSAI and (operating) frequencies of one or more neighboring cells (provided by the second access node and the third access node).

[0080] In box 502, it is assumed that the terminal device is initially operating in any RRC state. During this operation, in message 503, a core network entity (or node or function) of the core network sends a service announcement of a specific MBS (hereinafter referred to as MBS1) to the terminal device via the first access node, and in box 504, the terminal device receives the service announcement. The core network node that initiates the transmission may be the AF (although the service announcement may also be sent via one or more other core network nodes). In response to or based on receiving the service announcement, the first access node may simply forward the service announcement to the terminal device (or, more generally, to one or more terminal devices). In box 504, when the terminal device is operating in the RRC connected state, the service announcement may be received by the terminal device in unicast; or when the terminal device is operating in any RRC state, the service announcement may be received as a broadcast transmission.

[0081] The service announcement may generally be defined as described in conjunction with the previous embodiments. That is, in this example scenario, the service announcement includes two FSAIs: FSAI1 and FSAI2. In addition, the service announcement includes an indication that FSAI2 is for a RedCap terminal device (and therefore may be used for RedCap-based cell reselection). The service announcement may be associated with a specific TMGI (for identifying an MBS session).

[0082] In message 505, a core network entity (or node or function) sends a broadcast MBS session establishment request for a session of MBS1 (hereinafter referred to as MBS session 1) to the first access node. The broadcast MBS session establishment request may be sent to the access node, for example, by the AF via zero or more other core network nodes. The broadcast MBS session establishment request includes at least one FSAI that is indicated as defined for RedCap terminal devices in the configuration information of box 501, and optionally one or more FSAIs that are not indicated as defined for RedCap terminal devices. In this particular example, the broadcast MBS session establishment request includes at least FSAI1 (not specifically for RedCap terminal devices) and FSAI2 (for RedCap terminal devices). Optionally, the broadcast MBS session establishment request may also include an indication that FSAI2 is for RedCap terminal devices (i.e., suitable for RedCap-based cell reselection). In box 506, the first access node receives the broadcast MBS session establishment request for the MBS session 1.

[0083] In some embodiments, for at least one of at least one FSAI (e.g., for FSAI2) or at least one frequency, the service announcement received by the terminal device in box 504 and / or the broadcast MBS session establishment request received by the first access node in box 506 includes: information about at least one bandwidth restriction condition, and the FSAI or frequency defined for the reduced capability terminal device meets the at least one bandwidth restriction condition. In other words, the service announcement and / or the broadcast MBS session establishment request may include granularity related to, for example, UE type restriction (implicitly defining at least one bandwidth restriction) or bandwidth restriction of MBS1 (e.g., 100 MHz bandwidth restriction).

[0084] The first access node triggers or initiates the transmission of the MBS session (i.e., MBS session 1) within the RedCap CFR in block 507 based on the information obtained in blocks 501 and / or 506. The information may include: at least one FSAI (FSAI2 in this example), and at least one indication indicating that the at least one FSAI is defined for a RedCap terminal device.

[0085] After triggering the transmission of the MBS session in box 507, the first access node sends one or more messages 508, 512 to one or more neighboring access nodes. Each of the one or more messages 508, 512 includes: at least one FSAI (FSAI2 in this example), and at least one indication indicating that the at least one FSAI is defined for a terminal device with reduced capabilities. In other words, the (multiple) FSAIs signaled to the (multiple) neighboring access nodes are supplemented with a RedCap indication (i.e., indicating that the associated FSAI is for a RedCap terminal device). In the illustrated example, the one or more neighboring access nodes include a second access node and a third access node. The content of the one or more messages 508, 512 can be derived or generated based on the configuration of the first access node and / or the broadcast MBS session establishment request 505.

[0086] The one or more messages 508, 512 may be, or specifically include, one or more Xn setup and / or modification messages. In other words, when making a new Xn connection (Xn setup) with another access node, or making a new Xn connection (Xn modification) for an existing Xn connection, the first access node sends FSAI2 in the Xn setup or modification message 508, 512, as well as an implicit or explicit indication that it is currently in use (i.e., the first access node sends a broadcast setup and transmission trigger FSAI information to the neighboring access nodes). It is worth noting that if the first access node does not start transmission in RedCap CFR, it will not send FSAI2 to any neighboring access node. Therefore, any neighboring access node can determine that (multiple) RedCap CFRs are in use based on the received FSAI2.

[0087] exist Figure 5 In the example, in box 509, the second access node receives a message from the first access node (e.g., a message to establish or modify for Xn), the message including FSAI2 and an indication that FSAI2 is currently in use, and in box 513, the third access node receives a message (e.g., a message to establish or modify for Xn), the message including FSAI2 and an indication that FSAI2 is currently in use.

[0088] In such Figure 5 In some embodiments where the FSAI2 and RedCap CFR shown in FIG. 5 are also in use in the second access node, the second access node may also send a message (e.g., an Xn setup or modify message) including FSAI2 and an indication that FSAI2 is currently in use by the second access node to the first access node in message 510. The message is received by the first access node in box 511. In other embodiments (i.e., when FSAI2 is not currently in use by the second access node), elements 510, 511 may be omitted.

[0089] In such Figure 5 In some embodiments where the FSAI1 shown in FIG. 5 and the associated (multiple) non-RedCap CFRs are in use in the third access node, in message 514, the third access node may also send a message (e.g., an Xn setup or modification message) to the first access node, the message including: FSAI1, and an indication that FSAI1 is currently in use by the third access node. In box 515, the message is received by the first access node. In other embodiments (i.e., when FSAI1 is not currently in use by the third access node), elements 514 and 515 may be omitted.

[0090] It should be noted that in the case of including elements 510, 511 and / or elements 514, 515, the broadcast MBS session establishment request may also be sent from the core network to the second access node and / or the third access node (similar to the example in FIG. 1 ). Figure 5 These broadcast MBS session establishment requests have been removed from the Figure 5 is omitted (i.e., Figure 5 An attempt is made to primarily illustrate the operation of the first access node rather than fully illustrating the operation of the first access node, the second access node, and the third access node).

[0091] exist( Figure 5 In some alternative embodiments (not depicted in FIG), the information exchange of elements 508 to 515 may occur before the transmission and reception of the broadcast MBS session establishment request (element 505, element 506). The content of the sent message 508 / 510 / 512 / 514 may be derived or generated based on the configuration of the sending access node.

[0092] In some embodiments, elements 508 to 515 may be omitted. For example, in some embodiments, it may be assumed that the configuration of the FSAI is (relatively) static, and thus the FSAI, and associated RedCap indication, need not be transmitted after initial configuration, or after transmission of a broadcast MBS session establishment request.

[0093] In message 516, the first access node sends at least a mapping between at least one FSAI defined for a terminal device with reduced capabilities and at least one frequency (i.e., a FSAI to frequency mapping). The mapping may have been generated or formed by the first access node based on a message received in box 511 and / or box 515 (e.g., an establishment or modification message for Xn). In box 516, the terminal device receives the mapping. Message 516 may be SIB21. The transmission of message 516 may correspond to a broadcast. In general, the information sent in message 516 may include a mapping between any FSAI received in box 511 and / or box 515 and the frequencies associated with these FSAIs. The same (multiple) FSAIs may also be defined in a service announcement (although the first access node itself cannot access the content of the service announcement). Figure 5 In the specific example, the information sent (in the form of SIB21) includes FSAI2 to f 2 Mapping, and FSAI1 to f 3 Mapping.

[0094] After receiving the mapping (e.g., SIB21), in block 518, the terminal device operates in an RRC idle or inactive state. Similar to as described in conjunction with previous embodiments, in block 519, the terminal device performs cell measurements with the first access node, the second access node, and the third access node. Based on these cell measurements and the service announcement (and the mapping if the service announcement does not contain a frequency), in block 520, the terminal device performs cell reselection. Figure 5 In the example, the terminal device can 2 is considered as the highest priority for cell reselection because this frequency is specifically defined for RedCap terminal devices. Alternatively, the terminal device can only select f only if FSAI2 meets the limitations of the terminal device (i.e., the terminal device meets at least one bandwidth limitation condition defined in the service announcement). 2 It is regarded as the highest priority for cell reselection. Fig. 6A and Figure 6B Let's discuss this cell reselection example.

[0095] Although in some embodiments, the use of RedCap / Non-RedCap CFR at the access node may correspond to a (relatively) static configuration, in other embodiments, the use of RedCap / Non-RedCap CFR may be more dynamically adjusted based on the decision of a given access node (i.e., it is not a static configuration). In this more dynamic embodiment, the indication of the FSAI to frequency mapping (e.g., used in SIB21 (message 516)) may be more dynamically adapted to enable appropriate cell reselection at the terminal device. To this end, in the Xn signaling that sends the configured FSAI to neighboring access nodes (elements 508 to 515), non-RedCap and / or (multiple) RedCap FSAI are included only if a given MBS is currently being sent in the corresponding CFR. In other words, the access nodes may not have to share all configured FSAIs in the Xn setup / modify messages sent to neighboring access nodes, but only the FSAI associated with the (multiple) CFRs currently in use.

[0096] Fig. 6A and Figure 6B The diagram shows the Figure 5 There are two alternative signaling scenarios for cell reselection in block 520. Therefore, Fig. 6A and Figure 6B The process can be Figure 5 After the process of elements 501 to 519 is completed, it is executed. RedCap terminal device (hereinafter referred to as terminal device), Fig. 6A and Figure 6B The first access node, the second access node and the third access node, and the core network may be combined as follows Figure 5 Defined by what is described.

[0097] refer to Fig. 6A , if combined with Figure 5 As described above, when the terminal device reselects a cell (ie, searches for a cell to be selected), the frequency f defined for the RedCap terminal device is given priority. 2 Therefore, in block 601, the terminal device initially attempts to use frequency f based on the results of cell measurement. 2 A suitable cell for cell reselection was found but failed. Next, the terminal device attempts to reselect on a frequency f that is not specifically defined for RedCap terminal devices. 3 That is, the terminal device knows that in addition to the preferred but unavailable frequency f 2 In addition, MBS1 / MBS Session 1 will use frequency f 3 The terminal device searches for the frequency f in block 602. 3 3 of the current cell 1 and reselects cell 3 in box 603. In other words, the terminal device transitions from the current cell 1 to the new cell 3. In box 604, the terminal device operates in an RRC inactive or idle state in cell 3. In other words, the terminal device begins to camp on cell 3. Finally, in message 605, the third access node sends MBS1 / MBS Session 1 to the terminal device via cell 3. In box 606, the terminal device receives MBS1 / MBS Session 1. In this example, it is assumed that the non-RedCap CFR of message 605 makes them compatible with RedCap terminal devices and their bandwidth limitations, and therefore reception of MBS1 / MBS Session 1 via cell 3 is successful. If this is not the case, MBS1 / MBS Session 1 cannot be successfully received.

[0098] refer to Figure 6B , if combined with Figure 5 and Fig. 6A As described above, the terminal device gives priority to the frequency f2 defined for the RedCap terminal device when reselecting a cell (ie, searching for a cell to be selected). Therefore, in block 611, the terminal device initially attempts to use the frequency f2 based on the result of the cell measurement. 2 Find a suitable cell for cell reselection. In this example, in block 611, it is assumed that the terminal device uses frequency f 2Successfully finds cell 2 suitable for cell reselection. The terminal device reselects cell 2 in box 612. In other words, the terminal device transitions from the current cell 1 to the new cell 2. In box 613, the terminal device operates in the RRC inactive or idle state in cell 2. In other words, the terminal device begins to camp on cell 2. Finally, in message 614, the second access node sends MBS1 / MBS session 1 to the terminal device via cell 2. In box 615, the terminal device receives MBS1 / MBS session 1. Due to the frequency f 2 It is defined specifically for RedCap terminal devices. Therefore, since the terminal device is a RedCap terminal device (with Fig. 6A ), so no compatibility occurs.

[0099] Figure 7 and Figure 8 Two alternative core network signaling scenarios between the MB-SMF, NEF and the AF of the core network for enabling cell reselection according to an embodiment are shown. Figure 7 and Figure 8 Illustrated is a process for creating an indication of an FSAI for RedCap specific cell reselection.The processes also enable, or cause, transmission of an MBS session establishment request from the AF to at least one access node, as discussed in connection with the previous embodiments. Figure 7 and Figure 8 The process can be combined with the execution Figures 2 to 5 , Fig. 6A and Figure 6B Any of the processes discussed have been performed before. It can be assumed Figure 7 and Figure 8 The AF provides at least one MBS.

[0100] exist Figure 7 In the signaling scenario, the AF is configured to provide the FSAI for the MBS (or MBS session). Figure 7 In the embodiment, it is assumed that the AF knows (eg, based on a predefined protocol) a specific MBS for a RedCap terminal device (and optionally a non-RedCap terminal device). In other words, the AF knows the UE type for which the MBS is targeted.

[0101] In elements 701 to 703, the AF sends an MBS session creation request to the MB-SMF via the NEF to enable the MBS session establishment request to be transmitted to at least one access node. Specifically, in message 701, the AF sends a first MBS session creation request to the NEF. Here, the first MBS session creation request includes: at least one FSAI, and at least one indication indicating that the at least one FSAI is defined for a RedCap terminal device. Optionally, the first MBS session creation request may also include: one or more FSAIs that are not specifically for RedCap terminal devices (i.e., they are not accompanied by an indication indicating that they will be defined for RedCap terminal devices). In box 702, the NEF receives the first MBS session creation request and, in message 703, sends a second MBS session creation request to the NEF. The content described above for the first MBS session creation request also applies to the second MBS session creation request (i.e., the NEF can effectively forward the content of the first MBS session creation request to the MB-SMF). Therefore, the second MBS session creation request also includes at least one FSAI and at least one (RedCap related) indication, and optionally, one or more FSAIs without such indications. The first MBS session creation request (message 701) may be a Nnef_MBS_NBSSession_Create_Request message. The second MBS session creation request (message 703) may be a Nmbsmf_MMBSSession_Create_Request message.

[0102] In some embodiments, for at least one FSAI of at least one FSAI defined for a RedCap terminal device, the first MBS session creation request and the second MBS session creation request may further include: information about at least one bandwidth restriction condition, and the FSAI (or frequency) defined for the RedCap terminal device complies with the at least one bandwidth restriction condition. In other words, the first MBS session creation request and the second MBS session creation request may include: granularity related to, for example, UE type restriction (implicitly defining at least one bandwidth restriction) or bandwidth restriction of an MBS1 session (e.g., 100MHz bandwidth restriction).

[0103] In block 704, the MB-SMF receives a second MBS session creation request from the NEF. Subsequently, the MB-SMF may Figure 7That is, the MB-SMF may then send a broadcast MBS session establishment request for the MBS, wherein the broadcast MBS session establishment request includes: at least one FSAI, and at least one indication indicating that the at least one FSAI is defined for a RedCap terminal device.

[0104] After reception in block 704, in message 705, the MB-SMF sends the first MBS session creation response back to the NEF. Upon receiving the first MBS session creation response in block 706, the NEF sends the second MBS session creation response back to the AF in message 707. In block 708, the AF receives the second MBS session creation response. The first MBS session creation response and the second MBS session creation response are only used to confirm that the second MBS session creation request was successfully received at the MB-SMF. The first MBS session creation response (message 705) may be a Nmbsmf_MMBSSession_Create_Response message. The second MBS session creation response (message 707) may be a Nnef_MBSSession_Create_Response message.

[0105] In some embodiments, elements 705 to 708 may be omitted.

[0106] As mentioned above, Figure 8 The diagram shows Figure 7 The fundamental difference between the two technical solutions is that in Figure 8 In the signaling scenario, AF is not configured as Figure 7 Instead, the FSAI is created by the MB-SMF.

[0107] refer to Figure 8 , similar to Figure 7, in elements 801 to 803, the AF sends an MBS session creation request to the MB-SMF via the NEF to enable the MBS session establishment request to be transmitted to at least one access node. However, here, the FSAI or the associated RedCap indication is not included in the (multiple) MBS session creation request because the AF is not aware of the FSAI or the associated RedCap indication. Therefore, more specifically, in message 801, the AF sends a first MBS session creation request to the NEF. In box 802, the NEF receives the first MBS session creation request and, in message 803, sends a second MBS session creation request to the NEF. Both the first MBS session creation request and the second MBS session creation request may not contain any FSAI or associated indication related to the MBS session to be created. The first MBS session creation request (message 801) may be a Nnef_MBS_NBSSession_Create_Request message. The second MBS session creation request (message 803) may be a Nmbsmf_MMBSSession_Create_Request message.

[0108] In block 804, the MB-SMF receives a second MBS session creation request from the NEF. Subsequently, in block 805, the MB-SMF generates (or creates, or determines) at least one FSAI for RedCap terminal devices, and optionally one or more FSAIs that are not (specifically) defined for RedCap terminal devices. The generation (or creation, or determination) may be based on preconfigured information, or based on some other indication received from the AF and indicating that the service is for RedCap / non-RedCap terminal devices. The preconfigured information may include a predefined mapping, which may be, for example, a mapping between an MBS service area and a FSAI. Alternatively, the predefined mapping may be a mapping between broadcast MBS session information (e.g., an application identifier, ID) and a FSAI, or a mapping between a combination of an MBS service area and broadcast MBS session information (e.g., an application identifier, ID) and (multiple) FSAIs. In addition, in block 806, the MB-SMF creates or generates at least one indication indicating that the at least one FSAI (determined in block 805) is defined for a RedCap terminal device.

[0109] In message 807, the MB-SMF sends the first MBS session creation response back to the NEF. Here, the first MBS session creation request includes: at least one FSAI for RedCap terminal devices (and optionally one or more non-RedCap specific FSAIs) created in box 805; and at least one (RedCap) indication created in box 806. When the first MBS session creation response is received in box 808, the NEF sends a second MBS session creation response to the AF in message 809. The second MBS session creation response also includes: at least one FSAI for RedCap terminal devices (and optionally one or more non-RedCap specific FSAIs) created in box 805; and at least one (RedCap) indication created in box 806. In box 810, the AF receives the second MBS session creation response. The AF can store the content of the second MBS session creation response to the memory. Therefore, the first MBS session creation response and the second MBS session creation response are here used not only to confirm that the second MBS session creation request is successfully received at the MB-SMF, but also to transmit the generated (multiple) FSAI and (multiple) indications back to the AF. The first MBS session creation response (message 807) may be a Nmbsmf_MMBSSession_Create_Response message. The second MBS session creation response (message 809) may be a Nnef_MBSSession_Create_Response message.

[0110] In some embodiments, elements 807 to 810 may be omitted.

[0111] It should be noted that although Figure 7 and Figure 8 The diagram shows session creation without policy control checking (PCC), but similar decisions can be made and similar processes can be applied during session creation with PCC. Figure 7 and / or Figure 8 Some of the signaling interactions between the AF and MB-SMF discussed may be subject to further inspection and the specific names of the messages may be different, but the basic operating principles remain the same.

[0112] The above-mentioned embodiments are based on the introduction of new indications for FSAI (or frequency) in the service announcement of MBS to indicate that a specific FSAI / frequency is used to guide the RedCap terminal device to the neighboring cell frequency where MBS is to be provided according to the limitations of the RedCap terminal device. Therefore, in the described embodiments, the RedCap-specific guidance is mainly driven and implemented by the core network. In other embodiments, this may not be the case. That is, in some other embodiments, the RedCap-specific guidance may be mainly driven and implemented by the RAN. In such embodiments, the RedCap-specific additional information may be omitted from the service announcement (i.e., the service announcement is not enhanced), and instead, the corresponding information may be determined by the serving access node and transmitted to the terminal device. In these embodiments, the service announcement may still provide information about the FSAI of general neighboring access nodes, although there is no specific indication of FSAI supporting RedCap.

[0113] Fig. 9 A process for performing an informed cell reselection decision according to an embodiment is illustrated. Fig. 9 The illustrated process may be performed by a terminal device (or UE) or a part thereof. Here, the terminal device may be Figure 1 The terminal device may be a RedCap terminal device or a non-RedCap terminal device. In the following, for simplicity, the execution Fig. 9 The entities of a process are called devices.

[0114] refer to Fig. 9 The functions shown in the figure may be performed after receiving a service announcement for an MBS session. The service announcement may have defined one or more FSAIs for the MBS session, but it may not include the FSAIs in combination with the previous embodiments (e.g., Figure 2 Therefore, the device still needs such information in order to be able to perform cell reselection in an optimal manner. The device may Fig. 9 At the start of the process (and during blocks 901, 902), the RRC operates in an RRC inactive or idle state.

[0115] In block 901, the apparatus receives neighbor cell frequency information. The neighbor cell frequency information includes a mapping between at least one neighbor cell frequency of at least one neighbor cell and at least one FSAI of at least one MBS session. Here and hereinafter, the neighbor cell frequency is an operating frequency of a neighbor cell of a serving cell of the apparatus. The neighbor cell frequency information may be associated with one or more neighboring access nodes. The neighbor cell frequency information may be received from an access node. The neighbor cell frequency information may be received as (part of) a broadcast transmission.

[0116] In block 902, the apparatus receives at least one indication. Each indication may be associated with a single neighboring cell or multiple neighboring cells (thus, at least one indication provides information about one or more different neighboring cells together). Each indication provides information about RedCap support capabilities associated with at least one FSAI or at least one MBS session, or at least information that can be used to determine the RedCap support capabilities. That is, each indication in the at least one indication indicates at least one of the following items:

[0117] For at least one FSAI or at least one MBS session, whether RedCap terminal equipment is supported,

[0118] at least one type of RedCap terminal device supported for at least one FSAI or at least one MBS session, or

[0119] • At least one size of CFR available for at least one FSAI or at least one MBS session.

[0120] Each of the bulleted types of information listed above may be indicated for each neighboring cell (ie, the information may be neighboring cell specific).

[0121] The type of RedCap terminal device may be associated with a bandwidth size or frequency band supported by the RedCap terminal device. For example, a type 1 device may be a RedCap terminal device supporting bandwidth size 1, and a type 2 device may be a RedCap terminal device supporting bandwidth size 2. In some embodiments, if any type of RedCap terminal device is not supported for at least one FSAI or at least one MBS session, the indication indicating at least one type of RedCap terminal device may obtain a null value (or other predefined value).

[0122] In some embodiments, at least one type of RedCap terminal device supporting CFR is associated with at least one (maximum) bandwidth size supported by the RedCap terminal device.

[0123] It should be noted that at least one size of CFR (or an equivalent CFR bandwidth) can be used by the device to determine whether to support general RedCap terminal devices or specific types of RedCap terminal devices by comparing the supported bandwidth of (specific types of) RedCap terminal devices with at least one size of CFR. Therefore, all the indication types listed above enable the device to consider the RedCap terminal device support capabilities of neighboring cells when performing cell reselection.

[0124] At least one indication in box 902 may be associated with (and provide information about) at least one neighboring cell. Each of the at least one indication in box 902 may be associated with a different neighboring cell (or a different set of one or more neighboring cells). Thus, a given indication defined for a neighboring cell may indicate at least one of the following: whether reduced-capability terminal devices are supported for at least one FSAI or at least one MBS session at the neighboring cell; at least one type of RedCap terminal device supported for at least one FSAI or at least one MBS session at the neighboring cell; or at least one size of CFR that may be used for at least one FSAI or at least one MBS session at the neighboring cell.

[0125] The at least one indication of block 902 may be received from an access node (eg, from an access node that transmits neighbor cell frequency information).The at least one indication of block 902 may be received as a broadcast transmission, or as part of a broadcast transmission.

[0126] In some embodiments, the information received in blocks 901 and 902 may form (different) parts of a single message. The single message may be, for example, a SIB21 message. The SIB21 message may also include a mapping between at least one FSAI and at least one frequency defined for a RedCap terminal device according to a previous service announcement.

[0127] In some embodiments, the information received in blocks 901 and 902 (e.g., in the form of a SIB21 message) corresponds to information about at least one neighbor cell frequency, and for each of the at least one neighbor cell frequency, corresponds to one or more data sets. The at least one neighbor cell frequency may be associated with one or more different neighbor cells provided by a single neighbor access node or one or more different neighbor access nodes. Each data set associated with a given neighbor cell frequency includes an FSAI for an MBS session, and the at least one indication of block 902 that explicitly or implicitly describes support for a RedCap terminal device.

[0128] In block 903, the apparatus performs a cell reselection procedure based on cell measurements and neighbor cell frequency information, and at least one indication.

[0129] The cell measurements of box 903 can be performed by the device itself. The cell measurements may include measurements of signals sent by one or more access nodes that provide neighboring cells (i.e., neighboring relative to the current serving cell of the device). The cell measurements may include measurements of, for example, at least one of the following items: reference signal received power (RSRP), reference signal receiver quality (RSRQ), signal-to-noise ratio (SNR), or signal-to-interference-plus-noise ratio (SINR). The cell measurements may include measurements involving one or more (radio) frequencies (used in one or more neighboring cells). The cell measurements may include any cell measurements performed in an RRC inactive or idle state, as defined in 3GPP TS 38.306 and / or TS 38.304.

[0130] In some embodiments, the apparatus is a RedCap terminal device, and at least one indication of box 902 indicates support for RedCap terminal devices for at least one FSAI, without indicating at least one size of CFR for at least one FSAI and at least one type of RedCap terminal device supported for at least one FSAI (i.e., only basic information about RedCap support is provided). In such embodiments, during the cell reselection process of box 903, the apparatus may give priority to any neighboring cell frequency associated with at least one indication indicating support for at least one FSAI or at least one MBS session of a terminal device with reduced capabilities. In other words, any neighboring cell frequency associated with at least one FSAI or at least one MBS session indicated as a terminal device supporting reduced capabilities may be given priority. Alternatively, during the cell reselection process of box 903, the apparatus may give priority to any neighboring cell frequency associated with at least one indication indicating support for at least one FSAI or at least one MBS session of a terminal device with reduced capabilities only when the BWP restriction (or other restriction) of the terminal device allows the terminal device to receive MBS in the associated neighboring cell.

[0131] In some embodiments, the apparatus is a RedCap terminal device, and at least one indication of block 902 indicates at least one size of CFR for at least one FSAI or at least one MBS session. In such embodiments, during the cell reselection process of block 903, the apparatus may prioritize at least one neighboring cell frequency (or any neighboring cell frequency) associated with a size of CFR supported by the RedCap terminal device (i.e., the apparatus).

[0132] In some embodiments, the apparatus is a RedCap terminal device, and at least one indication of block 902 indicates at least one type of reduced-capability terminal device supported for at least one FSAI or at least one MBS session. In such embodiments, during the cell reselection process of block 903, the apparatus may prioritize at least one neighboring cell frequency (or any neighboring cell frequency) associated with the type of RedCap terminal device corresponding to the RedCap terminal device (i.e., the apparatus).

[0133] In some embodiments, both of the prioritization functions discussed in the previous two paragraphs may be implemented.

[0134] In some embodiments, the apparatus is a non-RedCap terminal device (i.e., a terminal device that is not defined as a RedCap terminal device). In such an embodiment, during the cell reselection process of box 903, the apparatus may give priority to at least one neighboring cell frequency (or any neighboring cell frequency) that cannot support a RedCap terminal device. In this way, any neighboring cell frequency defined for a RedCap terminal device is still available for a RedCap terminal device (for a RedCap terminal device, the selection of neighboring cell frequencies is more limited than for a non-RedCap terminal device). Whether a given neighboring cell frequency supports a RedCap terminal device can be determined based on at least one indication and neighboring cell frequency information. Additionally or alternatively, during the cell reselection process of box 903, the apparatus (which is a non-RedCap terminal device) may avoid or ignore any neighboring cell frequency that supports a RedCap terminal device.

[0135] Fig.10 A process for enabling an informed cell reselection decision according to an embodiment is shown. Fig.10 The illustrated process may be performed by an access node or a portion thereof. The access node may be, for example, Figure 1 104. In the following, for simplicity, the execution Fig.10 The entities of a process are called devices.

[0136] refer to Fig.10 In block 1001, the apparatus receives at least one indication from at least one neighboring access node. The at least one indication is used to provide information about the RedCap terminal device support capability of the at least one neighboring access node. That is, the at least one indication indicates at least one of the following items:

[0137] whether, for at least one FSAI or at least one MBS session at a neighboring access node among at least one neighboring access node, a terminal device with reduced capabilities is supported,

[0138] for at least one type of RedCap terminal device supported by at least one FSAI or at least one MBS session at a neighboring access node (or in a neighboring cell provided by a neighboring access node),

[0139] · CFR of at least one size for at least one FSAI or at least one MBS session at a neighboring access node, or

[0140] • At least one type of CFR currently in use by a neighboring access node for at least one FSAI or at least one MBS session.

[0141] Here, a neighboring access node may be defined as an access node that is neighboring to the device (and therefore provides one or more cells that are neighboring to one or more cells provided by the device). The at least one type of RedCap terminal device supported for at least one FSAI or at least one MBS session at the neighboring access node may have been determined based on the available CFR in the associated neighboring cell.

[0142] The at least one indication in block 1001 may be associated with (and provide information about) at least one neighboring access node. In block 1001, the apparatus may receive an indication from each of the at least one neighboring access node. Thus, each of the at least one indication in block 1002 may be associated with a different neighboring access node. Each indication may be associated with (i.e., provide information about) one or more neighboring cells provided by the neighboring access node.

[0143] In some embodiments, at least one indication of block 1001 may be included in an Xn setup or modification message or response.

[0144] In block 1002, the apparatus sends neighboring cell frequency information to a terminal device, the neighboring cell frequency information including a mapping between at least one neighboring cell frequency and at least one FSAI of at least one MBS session. Here, the neighboring cell frequency is an operating frequency of a neighboring cell of a serving cell provided by the apparatus. Generally, the neighboring cell frequency information sent in block 1002 may be combined with the above Fig. 9 The transmission of block 1002 may correspond to a broadcast transmission.

[0145] In block 1003, the apparatus sends at least one indication to a terminal device. For at least one neighboring cell provided by at least one neighboring access node, the at least one indication indicates at least one of the following items:

[0146] Whether reduced-capability terminal devices are supported for at least one FSAI or at least one MBS session,

[0147] at least one type of reduced capability terminal device supported for at least one FSAI or at least one MBS session, or

[0148] • At least one size of CFR available for at least one FSAI or at least one MBS session.

[0149] The apparatus may derive or generate at least one indication of block 1003 based on at least one indication of block 1001. Typically, at least one indication sent in block 1003 may be as described above in conjunction with Fig. 9 The transmission of block 1003 may correspond to a broadcast transmission.

[0150] In some embodiments, the information sent (or broadcast) in blocks 1002, 1003 may be contained in a single message. The single message may be, for example, a SIB21 message.

[0151] Fig.11 Another process for enabling an informed cell reselection decision according to an embodiment is illustrated. Fig.11 The process shown in can be performed by an access node or a part thereof. The access node can be, for example, Figure 1 104. In the following, for simplicity, the execution Figure 4 The entities of a process are called devices.

[0152] In block 1101, the apparatus receives at least one TMGI associated with at least one MBS session ongoing at the neighboring access node from each of one or more neighboring access nodes, and for each of the at least one TMGI, receives at least one indication related to RedCap terminal device support capabilities of the TMGI of the given neighboring access node. The at least one indication indicates at least one of the following:

[0153] For TMGI at adjacent access nodes, whether RedCap terminal equipment is supported,

[0154] for at least one type of RedCap terminal device supported by the TMGI at the adjacent access node, or

[0155] - CFR for at least one size of TMGI at a neighboring access node.

[0156] In block 1102, the apparatus sends neighbor cell frequency information to a terminal device, the neighbor cell frequency information including a mapping between at least one neighbor cell frequency and at least one FSAI of at least one MBS session. Here, the neighbor cell frequency is an operating frequency of a neighbor cell of a serving cell provided by the apparatus. The neighbor cell frequency information may be derived or generated based on at least one TMGI, at least one indication, and a mapping between at least one TMGI of at least one MBS session and at least one FSAI.

[0157] In block 1103, the apparatus sends at least one indication to the terminal device. The at least one indication indicates at least one of the following items:

[0158] Whether reduced-capability terminal devices are supported for at least one FSAI or at least one MBS session,

[0159] at least one type of reduced capability terminal device supported for at least one FSAI or at least one MBS session, or

[0160] • At least one size of common frequency resources CFR available for at least one FSAI or at least one MBS session.

[0161] In some embodiments, the information sent (or broadcast) in blocks 1102, 1103 may be contained in a single message. The single message may be, for example, a SIB21 message.

[0162] Fig.12 The diagram shows the signaling between a RedCap terminal device (hereinafter, for simplicity, referred to as a terminal device), a first access node, a second access node, a third access node, and a core network. The first access node, the second access node, and the third access node (for example, a gNB) can use corresponding (carrier) frequencies f 1 、f 2 and f 3 And the corresponding FSAI (FSAI2, FSAI2 and FSAI1) provide services for cells 1, 2 and 3. Here, FSAI2 can be a FSAI defined for RedCap terminal devices, and FSAI1 can be a FSAI defined not specifically for RedCap terminal devices. The terminal device can operate in cell 1. Functions related to the core network can be performed by the application function (AF) of the core network communicating with the network exposure function (NEF) of the core network and the multicast / broadcast session management function (MB-SMF) of the core network. Although Fig.12 The communication scenario in which the first access node providing the (initial) service cell for the terminal device has two adjacent access nodes is shown. Fig.12 The described features and functionalities may also be equally applicable to the case where the first access node has a single neighboring access node, or has more than two neighboring access nodes.

[0163] refer to Fig.12 , in box 1201, it is assumed that the terminal device is initially operating in any RRC state. During this operation, in message 1202, a core network entity (or node or function) of the core network sends a service announcement of a specific MBS (hereinafter referred to as MBS1) to the terminal device via the first access node, and in box 1203, the terminal device receives the service announcement. The core network node that initiates the transmission may be the AF (although the service announcement may also be sent via one or more other core network nodes). In response to or based on receiving the service announcement, the first access node may simply forward the service announcement to the terminal device (or, more generally, to one or more terminal devices). In box 1203, the service announcement may be received by the terminal device in unicast when the terminal device is operating in the RRC connected state; or the service announcement may be received as a broadcast transmission when the terminal device is operating in any RRC state.

[0164] In this example scenario, the service announcement includes two FSAIs: FSAI1 and FSAI2. Figure 5 In contrast, the service announcement does not include any indication that the FSAI2 is for a RedCap terminal device. In other words, the service announcement may be a "regular" service announcement without additional functionality. The service announcement may be associated with a specific TMGI (for identifying an MBS session).

[0165] In message 1204, the core network entity (or node or function) sends a broadcast MBS session establishment request for a session of MBS1 (hereinafter referred to as MBS session 1) to the first access node. The broadcast MBS session establishment request may be sent to the access node, for example, by the AF via zero or more other core network nodes. The broadcast MBS session establishment request includes one or more FSAIs. In this particular example, the broadcast MBS session establishment request includes at least FSAI1 and FSAI2. In this embodiment (compared to, for example, Figure 5 In contrast to the embodiment of FIG. 12 , the RedCap terminal device is not yet aware of its ability to support one or more FSAIs (eg, FSAI1 and FSAI2). In block 1205 , the first access node receives a broadcast MBS session establishment request for the MBS session 1 .

[0166] In block 1206, the first access node triggers or initiates transmission of an MBS session (ie, MBS Session 1) within the RedCap CFR. The transmission may be triggered or initiated based on an OAM configuration.

[0167] After triggering the transmission of the MBS session in box 1206, the first access node sends one or more messages 1207, 1211 to one or more neighboring access nodes (in this example, two messages 1207, 1211 are sent to two neighboring access nodes, respectively). Each of the one or more messages 1207, 1211 includes: at least one FSAI (i.e., FSAI2 in the example shown), and at least one indication indicating that at least one FSAI is defined for a terminal device with reduced capabilities. In other words, the (multiple) FSAIs sent to the (multiple) neighboring access nodes are supplemented with a RedCap indication (i.e., indicating that the associated FSAI is for a RedCap terminal device). In the example shown, the one or more neighboring access nodes include a second access node and a third access node. The content of the one or more messages 1207, 1211 can be derived or generated based on the configuration of the first access node and the broadcast MBS session establishment request 1204.

[0168] The one or more messages 1207, 1211 may be, or specifically include, one or more Xn setup and / or modification messages. In other words, when making a new Xn connection (Xn setup) with another access node, or making a new Xn connection (Xn modification) for an existing Xn connection, the first access node sends FSAI2 in the Xn setup or modification message 1207, as well as an implicit or explicit indication that it is currently in use (i.e., the first access node sends a broadcast setup and transmission trigger FSAI information start to the neighboring access nodes). It is worth noting that if the first access node does not start transmission in RedCap CFR, it will not send FSAI2 to any neighboring access node. Therefore, any neighboring access node can determine that (multiple) RedCap CFRs are in use based on the received FSAI2.

[0169] In this embodiment, one or more messages 1207, 1211 may include a combination of Fig.10 Box 1001 and / or Fig.11 In this example, since the first access node is currently using RedCap CFR with FSAI2 and MBS session 1, each of the one or more messages 1207, 1211 may include at least one indication indicating at least one of the following items:

[0170] For FSAI2 or MBS session 1 at the first access node, supporting RedCap terminal devices,

[0171] Supporting at least one type of RedCap terminal device for FSAI2 or MBS session 1 at the first access node (or in a neighboring cell provided by the first access node),

[0172] a CFR of at least one size for FSAI 2 or MBS Session 1 at the first access node,

[0173] • At least one type of CFR for FSAI 2 or MBS session 1 that is currently in use by the first access node.

[0174] In some embodiments, the type of CFR in use may have another granularity, for example, it may indicate (implicitly or explicitly) compliance with UE type restrictions, or compliance with predefined bandwidth restrictions (e.g., 100 MHz bandwidth restrictions). It may be assumed that each UE type is associated with one or more bandwidths or frequency bands supported by the UE. In other words, one or more messages 1207, 1211 may include bandwidth restriction conditions as discussed in conjunction with the above embodiments.

[0175] In block 1208, the second access node receives a message (e.g., a setup or modification message for Xn) from the first access node, the message including FSAI2 and at least one indication. Similarly, in block 1212, the third access node receives a message (e.g., a setup or modification message for Xn) from the first access node, the message including FSAI2 and at least one indication. In respective messages 1209, 1213, the second access node and the third access node send response messages (e.g., a setup or modification message for Xn) back to the first access node. In blocks 1210, 1214, the response messages 1209, 1213 are received by the first access node.

[0176] exist Fig.12 In the example of , it is assumed that the second access node is currently using RedCap CFR, and the third access node is currently using non-RedCap CFR. Therefore, the response message 1209 (e.g., a setup or modification message for Xn) may include at least one indication similar to messages 1207 and 1211, indicating at least one of the following items:

[0177] For FSAI2 or MBS session 1 at the second access node, support for RedCap terminal devices,

[0178] for at least one type of RedCap terminal device supported by FSAI2 or MBS Session 1 at the second access node (or in a neighboring cell provided by the first access node),

[0179] a CFR of at least one size for FSAI 2 or MBS Session 1 at the second access node,

[0180] • At least one type of CFR for FSAI2 or MBS Session 1 that is currently in use by the second access node.

[0181] In this example, since the third access node is currently using non-RedCap CFR with FSAI1 and MBS session 2, the response message 1213 (e.g., an establishment or modification message for Xn) may include at least one indication indicating at least one of the following:

[0182] For FSAI1 or MBS session 2 at the first access node, RedCap terminal devices are not supported (i.e., for FSAI1 or MBS session 2 at the first access node, only non-RedCap terminal devices are supported),

[0183] For FSAI1 or MBS session 2 at the third access node, no type of RedCap terminal device is supported,

[0184] · CFR of at least one size for FSAI1 or MBS Session 2 at the third access node,

[0185] • At least one type of CFR for FSAI2 or MBS Session2 that is currently in use by the second access node.

[0186] In some embodiments, the information listed in the previous paragraph may be omitted from message 1213. Message 1213 may be a conventional Xn setup or modification message. In these embodiments, the third access node may be an access node as defined in 3GPP Release 17 (without additional functionality).

[0187] In some embodiments, one or more of the messages 1209, 1213 may also include bandwidth limitation conditions as discussed in conjunction with the above embodiments.

[0188] Based on the information received in (multiple) messages 1209 and / or 1213, in message 1215, the first access node sends a SIB21 message for cell reselection to at least one terminal device via at least one access node. Here, the SIB21 message includes neighboring cell frequency information related to cells provided by the second access node and the third access node, and (implicitly or explicitly) at least one indication indicating possible RedCap terminal device support associated with the FSAI or MBS session of the second access node and the third access node. The at least one terminal device includes at least Fig.12The RedCap terminal device illustrated in FIG. The transmission of message 1215 may correspond to a broadcast. The transmission (or broadcast) may be performed periodically or periodically. In general, the transmission of SIB21 message 1215 may correspond to the broadcast as discussed above. Fig.10 The neighboring cell frequency information and the at least one indication may be combined as follows: Fig.10 Defined by what is described.

[0189] In box 1216, the (RedCap) terminal device receives a SIB21 message. After receiving the SIB21 message, in box 1217, the terminal device operates in an RRC idle or inactive state and receives a broadcast MBS session (MBS Session 1) from cell 1 of the first access node. Similar to as described in conjunction with the previous embodiments, in box 1218, the terminal device utilizes the first access node, the second access node, and the third access node to perform cell measurements. Based on these cell measurements and the SIB21 message (and optional service announcement), in box 1219, the terminal device performs cell reselection. Fig.12 In the example, Figure 5 Similar to the example, the terminal device can 2 is considered as the highest priority for cell reselection because this frequency is specifically defined for RedCap terminal devices. Alternatively, the terminal device can only select f only if FSAI2 meets the limitations of the terminal device (i.e., the terminal device meets at least one bandwidth limitation condition defined in (multiple) messages 1209 and / or 1213). 2 Considered as the highest priority for cell reselection.

[0190] Combined with the above Fig. 6A and Figure 6B The examples of cell reselection discussed above can also be applied here (ie, in combination with Fig.12 1219), but with some modifications. In other words, Fig. 6A and Figure 6B Any process in Fig.12 Elements 1201 to 1218 are executed after completion.

[0191] In some simplified embodiments, the access node is configured via OAM with information that specific(s) FSAIs are associated with RedCap terminal devices (and optionally with appropriate bandwidths) (i.e., they support RedCap terminal devices). Based on this configuration, when receiving signaling to start an MBS session including any of those specific FSAIs, the access node will send the service (i.e., MBS) in RedCap CFR and using bandwidth suitable for RedCap UEs, and may also transmit in non-RedCap CFR.

[0192] The embodiments discussed above provide at least some of the following technical advantages. These embodiments allow different cell reselection prioritizations to be performed by RedCap and non-RedCap terminal devices, which in turn results in proper (i.e., correct or appropriate) broadcast reception by terminal devices in RRC inactive or idle states. These embodiments enable access nodes to make intelligent decisions about which CFR(s) to utilize for different broadcast services.

[0193] With the help of Figures 2 to 5 , Fig. 6A , Figure 6B ,as well as Figures 7 to 12 The described boxes, related functions and information exchanges are not in absolute chronological order, and some of them may be executed simultaneously or in an order different from the given order. Other functions may also be performed between or within them, and other information may be sent and / or other rules may be applied. Some boxes in the box, or parts of the box, or one or more pieces of information may also be omitted, or replaced by corresponding boxes, or parts of the box, or one or more pieces of information.

[0194] Fig.13 An apparatus 1301 according to some embodiments is provided. Specifically, Fig.13 The apparatus 1301 may be illustrated as a terminal device, an access node, or a core network node (eg, AF, NEF, or MB-SMF). Alternatively, Fig.13 The apparatus 1301 may be illustrated as part of a terminal device, an access node, or a core network node (eg, an AF, NEF, or MB-SMF).

[0195] The apparatus 1301 may include one or more communication control circuit systems 1320 (such as at least one processor) and at least one memory 1340, including one or more algorithms 1331 (instructions), such as computer program codes (software), wherein the at least one memory 1340 and the computer program code (software) are configured to, together with the at least one processor, enable the apparatus 1301 to perform any of the exemplary functions of the above-mentioned apparatus (e.g., a terminal device, an access node, an AF, a NEF, or an MB-SMF). The at least one memory 1340 may also include at least one database 1332.

[0196] When one or more communication control circuit systems 1320 include more than one processor, the device 1301 can be a distributed device in which the processing of tasks occurs in more than one physical unit. Each processor in at least one processor may include one or more processor cores. The processing core may include, for example, a Cortex-A8 processing core manufactured by ARM Holdings, or a Zen processing core designed by Advanced Micro Devices Corporation. One or more communication control circuit systems 1320 may include at least one Qualcomm Snapdragon and / or Intel Atom processor. One or more communication control circuit systems 1320 may include at least one application specific integrated circuit (ASIC). One or more control circuit systems 1320 may include at least one field programmable gate array (FPGA).

[0197] refer to Fig.13 The one or more communication control circuit systems 1320 of the device 1301 are configured to use one or more separate circuit systems, with the aid of Figures 2 to 5 , Fig. 6A , Figure 6B and Figures 7 to 12 To perform the above functions, any one of Figure 5 , Fig. 6A , Figure 6B , Figure 7 , Figure 8 and Fig.12 In the case of the device 1301, one or more communication control circuit systems 1320 are configured to perform the functions of at least one of the devices shown in the figure. According to different embodiments, it is also feasible to use a specific integrated circuit, such as an ASIC (application-specific integrated circuit) or other components and devices to implement the functions.

[0198] refer to Fig.13, the device 1301 may also include different interfaces 1310, such as one or more communication interfaces, including hardware and / or software, for implementing communication connectivity according to one or more communication protocols. Specifically, when the device 1301 is a terminal device or a part thereof, the one or more communication interfaces 1310 may include, for example, a communication interface that provides a connection between the device 1301 and one or more access nodes, for providing a connection to a core network (including, for example, MB-SMF, NEF, and AF). If the device 1301 is an access node or a part thereof, the one or more communication interfaces 1310 may include, for example, a communication interface between the device 1301 and one or more terminal devices, and a communication interface between the device 1301 and one or more core network nodes (including, for example, MB-SMF, NEF, and AF). The one or more communication interfaces 1310 may include standard well-known components, such as amplifiers, filters, frequency converters, (de)modulators and encoder / decoder circuits controlled by corresponding control units, and one or more antennas. The device 1301 may also include one or more user interfaces.

[0199] refer to Fig.13 , memory 1340 may be implemented using any suitable data storage technology, such as semiconductor-based memory devices, flash memory, magnetic memory devices and systems, optical memory devices and systems, fixed memory, and removable memory.

[0200] As used in this application, the term "circuitry" may refer to one or more or all of the following: (a) a hardware circuit implementation only, such as an implementation in analog and / or digital circuitry only; and (b) a combination of hardware circuitry and software (and / or firmware), such as (where applicable): (i) a combination of analog and / or digital hardware circuitry and software / firmware, and (ii) any portion of a hardware processor(s) with software, including digital signal processor(s), software, and memory(s), which work together to enable an apparatus (such as a terminal device or access node) to perform various functions; and (c) hardware circuitry and processor(s), such as microprocessor(s), or a portion of a microprocessor(s), which requires software (e.g., firmware) to operate, but the software may not be present when the software is not required for operation. This definition of "circuitry" applies to all uses of the term in this application, including in any claims. As another example, as used in this application, the term "circuitry" also covers an implementation of merely a hardware circuit or processor (or multiple processors), or a portion of a hardware circuit or processor and its (or their) accompanying software and / or firmware.

[0201] In one embodiment, in combination Figures 2 to 5, Fig. 6A , Figure 6B and Figures 7 to 12 At least some of the described processes may be performed by an apparatus including corresponding components for performing at least some of the described processes. Some example components for performing these processes may include at least one of the following: a detector, a processor (including dual-core and multi-core processors), a digital signal processor, a controller, a receiver, a transmitter, an encoder, a decoder, a memory, a RAM, a ROM, software, firmware, a display, a user interface, a display circuit system, a user interface circuit system, a user interface software, a display software, a circuit, a filter (low pass, high pass, band pass and / or band stop), a sensor, a circuit system, an inverter, a capacitor, an inductor, a resistor, an operational amplifier, a diode, and a transistor. In one embodiment, the at least one processor, the memory, and the computer program code form a processing component or include one or more computer program code portions for performing the processing according to Figures 2 to 5 , Fig. 6A , Figure 6B and Figures 7 to 12 Any one of the embodiments or its operation to perform one or more operations. In some embodiments, at least some of the processes can be implemented using discrete components.

[0202] According to one embodiment, an apparatus (e.g., a terminal device, or UE, or a portion thereof) is provided, the apparatus comprising means for performing the following:

[0203] A service announcement of a multicast broadcast service MBS is received, wherein the service announcement includes:

[0204] at least one frequency selective area identifier FSAI and at least one indication that the at least one FSAI is defined for a reduced capability terminal device, or

[0205] - at least one frequency, and at least one indication indicating that the at least one frequency is defined for a reduced capability terminal device;

[0206] The component is further configured to: perform a cell reselection process based on cell measurement and service announcement.

[0207] According to one embodiment, an apparatus (e.g., an AF, or a portion thereof) is provided, the apparatus comprising means for performing the following operations:

[0208] A service announcement of a multicast broadcast service MBS is received, wherein the service announcement includes:

[0209] at least one frequency selective area identifier FSAI and at least one indication that the at least one FSAI is defined for a reduced capability terminal device, or

[0210] - at least one frequency, and at least one indication indicating that the at least one frequency is defined for a reduced capability terminal device;

[0211] The component is further configured to: perform a cell reselection process based on cell measurement and service announcement.

[0212] According to one embodiment, an apparatus (e.g., an access node, or a portion thereof) is provided, the apparatus comprising means for performing the following:

[0213] Receiving a broadcast MBS session establishment request for a multicast broadcast service MBS session from a core network function, wherein the broadcast MBS session establishment request comprises: at least one frequency selection area identifier FSAI, and at least one indication indicating that the at least one FSAI is defined for a reduced capability terminal device; or

[0214] receiving a broadcast MBS session establishment request for an MBS session from a core network, and configuration information from an operations, administration and management (OAM) entity, wherein the broadcast MBS session establishment request comprises at least one FSAI, and the configuration information comprises at least one indication indicating that the at least one FSAI is defined for a reduced capability terminal device; and wherein the component is further configured to perform:

[0215] Based on the at least one FSAI and the at least one indication, transmission of an MBS session within the reduced capability common frequency resources CFR is triggered.

[0216] According to one embodiment, an apparatus (e.g., an MB-SMF, or a portion thereof) is provided, the apparatus comprising means for performing the following:

[0217] receiving an MBS session creation request for a multicast broadcast service MBS session;

[0218] In response to or based on the receiving, generating, for the MBS session, at least one frequency selection area identifier FSAI terminal device defined for a reduced capability terminal device and at least one indication indicating that the at least one FSAI is defined for a reduced capability terminal device; and

[0219] A broadcast MBS session establishment request for an MBS session is sent to at least one access node, wherein the broadcast MBS session establishment request includes at least one FSAI and at least one indication.

[0220] According to one embodiment, an apparatus (e.g., a terminal device, or a portion thereof) is provided, the apparatus comprising means for performing the following:

[0221] receiving neighbor cell frequency information, the neighbor cell frequency information comprising: a mapping between at least one neighbor cell frequency and at least one frequency selection area identifier FSAI of at least one multicast broadcast service MBS session, wherein the neighbor cell frequency is an operating frequency of a neighbor cell of a serving cell of the apparatus;

[0222] Receiving at least one indication, the at least one indication indicating at least one of the following for at least one neighboring cell:

[0223] Whether reduced-capability terminal devices are supported for at least one FSAI or at least one MBS session,

[0224] at least one type of reduced capability terminal device supported for at least one FSAI or at least one MBS session, or

[0225] at least one size of common frequency resources CFR available for at least one FSAI or at least one MBS session; and

[0226] A cell reselection procedure is performed based on the cell measurement and neighbor cell frequency information, and the at least one indication.

[0227] According to one embodiment, an apparatus (e.g., an access node or a portion thereof) is provided, the apparatus comprising means for performing the following:

[0228] At least one indication is received from at least one neighboring access node, the at least one indication indicating at least one of the following:

[0229] whether, for at least one frequency selective area identification FSAI or at least one multicast broadcast service MBS session at a neighboring access node among at least one neighboring access node, a reduced capability terminal device is supported,

[0230] for at least one type of reduced capability terminal device supported by at least one FSAI or at least one MBS session at a neighboring access node,

[0231] Common frequency resources CFR of at least one size for at least one FSAI or at least one MBS session at a neighboring access node,

[0232] At least one type of CFR currently in use by a neighboring access node for at least one FSAI or at least one MBS session;

[0233] Sending neighbor cell frequency information to a terminal device, the neighbor cell frequency information comprising: a mapping between at least one neighbor cell frequency and at least one FSAI of at least one MBS session, wherein the neighbor cell frequency is an operating frequency of a neighbor cell of a service cell provided by the apparatus; and

[0234] Sending at least one indication to a terminal device, the at least one indication indicating at least one of the following items for at least one neighboring cell provided by at least one neighboring access node:

[0235] Whether reduced-capability terminal devices are supported for at least one FSAI or at least one MBS session,

[0236] at least one type of reduced capability terminal device supported for at least one FSAI or at least one MBS session, or

[0237] • At least one size of CFR available for at least one FSAI or at least one MBS session.

[0238] According to one embodiment, an apparatus (e.g., an access node, or a portion thereof) is provided, the apparatus comprising means for performing the following:

[0239] receiving, from each of the one or more neighboring access nodes, at least one temporary mobile group identity (TMGI) associated with at least one multicast broadcast service (MBS) session ongoing at the neighboring access node, and receiving, for each of the at least one TMGI, at least one indication indicating at least one of:

[0240] Whether to support reduced-capability terminal devices for TMGI at adjacent access nodes,

[0241] for at least one type of reduced-capability terminal device supported by the TMGI at the neighboring access node, or

[0242] · CFR for at least one size of TMGI at a neighboring access node;

[0243] sending neighbor cell frequency information to a terminal device, the neighbor cell frequency information comprising a mapping between at least one neighbor cell frequency and at least one FSAI of at least one MBS session, wherein the neighbor cell frequency is an operating frequency of a neighbor cell of a serving cell provided by the apparatus, and the neighbor cell frequency information is based on at least one TMGI, at least one indication, and a mapping between at least one TMGI of at least one MBS session and at least one FSAI; and

[0244] Sending at least one indication of at least one neighboring cell provided by one or more neighboring access nodes to a terminal device, wherein for the neighboring cell (or according to at least one neighboring cell), the at least one indication indicates at least one of the following items:

[0245] Whether reduced-capability terminal devices are supported for at least one FSAI or at least one MBS session,

[0246] at least one type of reduced capability terminal device supported for at least one FSAI or at least one MBS session, or

[0247] • At least one size of common frequency resources CFR available for at least one FSAI or at least one MBS session.

[0248] The embodiments as described may also be implemented in whole or at least in part in the form of a computer process defined by a computer program or parts thereof. Figures 2 to 5 , Fig. 6A , Figure 6B and Figures 7 to 12 Embodiments of the described methods can be performed by executing at least a portion of a computer program including corresponding instructions. The computer program can be provided as a computer-readable medium including program instructions stored thereon, or as a non-transient computer-readable medium including program instructions stored thereon. The computer program can be in source code form, object code form, or in some intermediate form, and it can be stored in some carrier, which can be any entity or device capable of carrying the program. For example, the computer program can be stored on a computer program distribution medium readable by a computer or processor. For example, the computer program medium can be, for example but not limited to, a recording medium, a computer memory, a read-only memory, an electric carrier signal, a telecommunication signal, and a software distribution package. The computer program medium can be a non-transient medium. The coding of the software for executing the embodiment as shown and described is completely within the scope of ordinary technicians in the art.

[0249] According to one embodiment, a non-transitory computer-readable medium is provided having instructions stored thereon that, when executed by a computing device, cause the computing device to perform:

[0250] A service announcement of a multicast broadcast service MBS is received, wherein the service announcement includes:

[0251] at least one frequency selective area identifier FSAI and at least one indication that the at least one FSAI is defined for a reduced capability terminal device, or

[0252] - at least one frequency, and at least one indication indicating that the at least one frequency is defined for a reduced capability terminal device;

[0253] When the instructions are executed by the computing device, the computing device is further caused to: perform a cell reselection process based on the cell measurement and the service announcement.

[0254] According to one embodiment, a non-transitory computer-readable medium is provided having instructions stored thereon, which when executed by a computing device, cause the computing device to perform:

[0255] Sending a service announcement of a multicast broadcast service MBS to at least one terminal device via at least one access node, wherein the service announcement includes:

[0256] at least one frequency selective area identifier FSAI and at least one indication that the at least one FSAI is defined for a reduced capability terminal device, or

[0257] - at least one frequency defined for reduced capability terminal devices, and at least one indication indicating that the at least one frequency is defined for reduced capability terminal devices.

[0258] According to one embodiment, a non-transitory computer-readable medium is provided having instructions stored thereon, which when executed by a computing device, cause the computing device to perform:

[0259] Receiving a broadcast MBS session establishment request for a multicast broadcast service MBS session from a core network function, wherein the broadcast MBS session establishment request comprises: at least one frequency selection area identifier FSAI, and at least one indication indicating that the at least one FSAI is defined for a reduced capability terminal device; or

[0260] Receiving a broadcast MBS session establishment request for an MBS session of a core network, and configuration information from an operations, administration and management (OAM) entity, wherein the broadcast MBS session establishment request includes at least one FSAI, and the configuration information includes at least one indication indicating that the at least one FSAI is defined for a reduced capability terminal device; and wherein the instructions, when executed by a computing device, further cause the computing device to further perform:

[0261] Transmission of an MBS session within the reduced capability common frequency resources CFR is triggered based on the at least one FSAI and the at least one indication.

[0262] According to one embodiment, a non-transitory computer-readable medium is provided having instructions stored thereon, which when executed by a computing device, cause the computing device to perform:

[0263] receiving an MBS session creation request for a multicast broadcast service MBS session;

[0264] In response to or based on the receiving, generating, for the MBS session, at least one frequency selection area identifier FSAI defined for a reduced capability terminal device and at least one indication indicating that the at least one FSAI is defined for a reduced capability terminal device; and

[0265] A broadcast MBS session establishment request for an MBS session is sent to at least one access node, wherein the broadcast MBS session establishment request includes at least one FSAI and at least one indication.

[0266] The term "non-transitory" as used herein is a limitation of the medium itself (ie, tangible, not a signal), not a limitation on data storage persistence (eg, RAM vs. ROM).

[0267] According to one embodiment, a method is provided, comprising:

[0268] Receive a service announcement of a multicast broadcast service MBS, where the service announcement includes:

[0269] at least one frequency selective area identifier FSAI and at least one indication that the at least one FSAI is defined for a reduced capability terminal device, or

[0270] - at least one frequency, and at least one indication indicating that the at least one frequency is defined for a reduced capability terminal device;

[0271] The method further includes: performing a cell reselection process based on cell measurement and service announcement.

[0272] According to one embodiment, a method is provided, comprising:

[0273] Sending a service announcement of a multicast broadcast service MBS to at least one terminal device via at least one access node, wherein the service announcement includes:

[0274] at least one frequency selective area identifier FSAI and at least one indication that the at least one FSAI is defined for a reduced capability terminal device, or

[0275] - at least one frequency defined for reduced capability terminal devices, and at least one indication indicating that the at least one frequency is defined for reduced capability terminal devices.

[0276] According to one embodiment, a method is provided, comprising:

[0277] Receiving a broadcast MBS session establishment request for a multicast broadcast service MBS session from a core network function, wherein the broadcast MBS session establishment request comprises: at least one frequency selection area identifier FSAI, and at least one indication indicating that the at least one FSAI is defined for a reduced capability terminal device; or

[0278] receiving a broadcast MBS session establishment request for an MBS session from a core network, and configuration information from an operations, administration and management (OAM) entity, wherein the broadcast MBS session establishment request comprises at least one FSAI, and the configuration information comprises at least one indication indicating that the at least one FSAI is defined for a reduced capability terminal device; and wherein the method further comprises:

[0279] Transmission of an MBS session within the reduced capability common frequency resources CFR is triggered based on the at least one FSAI and the at least one indication.

[0280] According to one embodiment, a method is provided, comprising:

[0281] receiving an MBS session creation request for a multicast broadcast service MBS session;

[0282] In response to or based on the receiving, generating, for the MBS session, at least one frequency selection area identifier FSAI defined for a reduced capability terminal device and at least one indication indicating that the at least one FSAI is defined for a reduced capability terminal device; and

[0283] A broadcast MBS session establishment request for an MBS session is sent to at least one access node, wherein the broadcast MBS session establishment request includes at least one FSAI and at least one indication.

[0284] Example 1: An apparatus, comprising: at least one processor; and at least one memory, the at least one memory storing instructions, which when executed by the at least one processor, causes the apparatus to at least perform:

[0285] receiving neighbor cell frequency information, the neighbor cell frequency information comprising: a mapping between at least one neighbor cell frequency and at least one frequency selection area identifier FSAI of at least one multicast broadcast service MBS session, wherein the neighbor cell frequency is an operating frequency of a neighbor cell of a serving cell of the apparatus;

[0286] Receiving at least one indication, the at least one indication indicating at least one of the following for at least one neighboring cell:

[0287] Whether reduced-capability terminal devices are supported for at least one FSAI or at least one MBS session,

[0288] at least one type of reduced capability terminal device supported for at least one FSAI or at least one MBS session, or

[0289] at least one size of common frequency resources CFR available for at least one FSAI or at least one MBS session; and

[0290] A cell reselection procedure is performed based on the cell measurement and neighbor cell frequency information, and the at least one indication.

[0291] Example 2: The apparatus of Example 1, wherein the neighbor cell frequency information and the at least one indication are received in a system information block 21 (SIB21) message.

[0292] Example 3: An apparatus according to Example 1 or 2, wherein the apparatus is a reduced capability terminal device.

[0293] Example 4: The apparatus of Example 3, wherein the at least one indication indicates support for reduced-capability terminal devices for at least one FSAI or at least one MBS session, without indicating any of the following: at least one size of CFR available for at least one FSAI or at least one MBS session; and at least one type of reduced-capability terminal devices supported for at least one FSAI or at least one MBS session; and wherein performing a cell reselection procedure comprises:

[0294] In a cell reselection procedure, priority is given to at least one neighbor cell frequency associated with at least one indication of a terminal device indicated as supporting reduced capabilities for at least one FSAI or at least one MBS session.

[0295] Example 5: The apparatus according to Example 3, wherein at least one indication indicates a terminal device of at least one size of CFR available for at least one FSAI or at least one MBS session, and / or at least one type of reduced capability supported for at least one FSAI or at least one MBS session; and wherein performing a cell reselection procedure comprises:

[0296] In the cell reselection procedure, priority is given to at least one neighbour cell frequency associated with the size of the CFR supported by the reduced capability terminal device and / or associated with the type of reduced capability terminal device corresponding to the reduced capability terminal device.

[0297] Example 6: The apparatus of example 1 or 2, wherein the apparatus is a non-reduced capability terminal device; and wherein performing a cell reselection procedure comprises:

[0298] During the cell reselection process, at least one neighboring cell frequency that cannot support the terminal device with reduced capability is prioritized based on the at least one indication and the neighboring cell frequency information.

[0299] Example 7: The apparatus according to any one of Examples 1 to 6, wherein the at least one memory and the instructions are configured to, together with the at least one processor, cause the apparatus to execute, before receiving the neighbor cell frequency information:

[0300] A service announcement for an MBS session is received, wherein the service announcement indicates at least one FSAI associated with the MBS session or at least one frequency associated with the MBS session, wherein the execution of the cell reselection procedure is further based on the service announcement.

[0301] Example 8: The apparatus of any one of Examples 1 to 7, wherein the at least one memory and the instructions are configured to, with the at least one processor, cause the apparatus to perform:

[0302] During the cell reselection process, the radio resource control (RRC) idle or inactive state is operated.

[0303] Example 9: An apparatus comprising:

[0304] at least one processor; and

[0305] at least one memory storing instructions that, when executed by at least one processor, cause the apparatus to at least perform:

[0306] At least one indication is received from at least one neighboring access node, the at least one indication indicating at least one of the following:

[0307] whether, for at least one frequency selective area identification FSAI or at least one multicast broadcast service MBS session at a neighboring access node among at least one neighboring access node, a reduced capability terminal device is supported,

[0308] for at least one type of reduced capability terminal device supported by at least one FSAI or at least one MBS session at a neighboring access node,

[0309] Common frequency resources CFR of at least one size for at least one FSAI or at least one MBS session at a neighboring access node,

[0310] At least one type of CFR currently in use by a neighboring access node for at least one FSAI or at least one MBS session;

[0311] Sending neighbor cell frequency information to a terminal device, the neighbor cell frequency information comprising: a mapping between at least one neighbor cell frequency and at least one FSAI of at least one MBS session, wherein the neighbor cell frequency is an operating frequency of a neighbor cell of a service cell provided by the apparatus; and

[0312] Sending at least one indication to a terminal device, the at least one indication indicating at least one of the following items for at least one neighboring cell provided by at least one neighboring access node:

[0313] Whether reduced-capability terminal devices are supported for at least one FSAI or at least one MBS session,

[0314] at least one type of reduced capability terminal device supported for at least one FSAI or at least one MBS session, or

[0315] • At least one size of CFR available for at least one FSAI or at least one MBS session.

[0316] Example 10: The apparatus of Example 9, wherein the at least one memory and the instructions are configured to, with the at least one processor, cause the apparatus to perform:

[0317] A broadcast MBS session establishment request for a multicast broadcast service MBS session is received from a core network function, wherein the broadcast MBS session establishment request includes: at least one FSAI associated with the MBS session.

[0318] Example 11: The apparatus of example 9 or 10, wherein the at least one memory and the instructions are configured to, with the at least one processor, cause the apparatus to perform:

[0319] receiving configuration information from an operations, administration and management (OAM) entity, wherein the configuration information comprises: at least one indication indicating that at least one FSAI associated with the MBS session is defined for a reduced capability terminal device; and

[0320] Based on the configuration information, the transmission of an MBS session within a CFR defined for the reduced capability terminal device is triggered.

[0321] Example 12: The apparatus according to example 10 or 11, wherein the at least one memory and the instructions are configured to, with the at least one processor, cause the apparatus to perform:

[0322] Sending at least one indication to at least one neighboring access node, the at least one indication indicating at least one of the following:

[0323] whether, for at least one FSAI or at least one MBS session at the device, reduced capability terminal equipment is supported,

[0324] for at least one type of reduced capability terminal equipment supported by at least one FSAI or at least one MBS session at the device, or

[0325] a CFR of at least one size for at least one FSAI or at least one MBS session at the device, or

[0326] • The type of CFR currently in use by the device for at least one FSAI or at least one MBS session.

[0327] Example 13: An apparatus comprising:

[0328] at least one processor; and

[0329] at least one memory storing instructions that, when executed by at least one processor, cause the apparatus to at least perform:

[0330] receiving, from each of the one or more neighboring access nodes, at least one temporary mobile group identity (TMGI) associated with at least one multicast broadcast service (MBS) session ongoing at the neighboring access node, and receiving, for each of the at least one TMGI, at least one indication indicating at least one of:

[0331] Whether to support reduced-capability terminal devices for TMGI at adjacent access nodes,

[0332] for at least one type of reduced-capability terminal device supported by the TMGI at the neighboring access node, or

[0333] · CFR for at least one size of TMGI at a neighboring access node;

[0334] sending neighbor cell frequency information to a terminal device, the neighbor cell frequency information comprising: a mapping between at least one neighbor cell frequency and at least one FSAI of at least one MBS session, wherein the neighbor cell frequency is an operating frequency of a neighbor cell of a serving cell provided by the apparatus, and the neighbor cell frequency information is based on at least one TMGI, at least one indication, and a mapping between at least one TMGI of at least one MBS session and at least one FSAI; and

[0335] Sending at least one indication for at least one neighboring cell provided by one or more neighboring access nodes to a terminal device, wherein for the at least one neighboring cell, the at least one indication indicates at least one of the following items:

[0336] Whether reduced-capability terminal devices are supported for at least one FSAI or at least one MBS session,

[0337] at least one type of reduced capability terminal device supported for at least one FSAI or at least one MBS session, or

[0338] • At least one size of common frequency resources CFR available for at least one FSAI or at least one MBS session.

[0339] Example 14: The apparatus of Example 13, wherein the at least one memory and the instructions are configured to, with the at least one processor, cause the apparatus to perform:

[0340] Sending at least one TMGI associated with at least one MBS session ongoing at the device to each of the one or more neighboring access nodes, and for each of the at least one TMGI associated with at least one MBS session ongoing at the device, sending at least one indication indicating at least one of the following:

[0341] For TMGI at the device, whether reduced-capability terminal devices are supported,

[0342] for at least one type of reduced-capability terminal device supported by TMGI at the device, or

[0343] • CFR for at least one size of TMGI at the device.

[0344] Example 15: The apparatus according to Example 13, wherein the at least one memory and the instructions are configured to, together with the at least one processor, cause the apparatus to execute, before transmitting the neighbor cell frequency information:

[0345] receiving a broadcast MBS session establishment request for the MBS session from a core network function, wherein the broadcast MBS session establishment request includes: at least one FSAI associated with the MBS session; and

[0346] Based on the broadcast MBS session establishment request and the at least one TMGI, and at least one indication received from one or more neighboring access nodes, a mapping between at least one TMGI and at least one FSAI for at least one MBS session is determined.

[0347] Example 16: The apparatus of Example 15, wherein the at least one memory and the instructions are configured to, with the at least one processor, cause the apparatus to perform:

[0348] receiving configuration information from an operations, administration, and management (OAM) entity, wherein the configuration information comprises at least one indication indicating that at least one FSAI associated with an MBS session supported by the apparatus is defined for a reduced capability terminal device; and

[0349] Based on the configuration information, the transmission of an MBS session within a CFR defined for the reduced capability terminal device is triggered.

[0350] Example 17: An apparatus according to any one of Examples 9 to 16, wherein the neighbor cell frequency information and the at least one indication are sent to the terminal device in a system information block 21 (SIB21) message.

[0351] Example 18: A method comprising:

[0352] receiving neighbor cell frequency information, the neighbor cell frequency information comprising: a mapping between at least one neighbor cell frequency and at least one frequency selection area identifier FSAI of at least one multicast broadcast service MBS session, wherein the neighbor cell frequency is an operating frequency of a neighbor cell of a serving cell of the apparatus;

[0353] Receiving at least one indication, the at least one indication indicating at least one of the following for at least one neighboring cell:

[0354] Whether reduced-capability terminal devices are supported for at least one FSAI or at least one MBS session,

[0355] at least one type of reduced capability terminal device supported for at least one FSAI or at least one MBS session, or

[0356] at least one size of common frequency resources CFR available for at least one FSAI or at least one MBS session; and

[0357] A cell reselection procedure is performed based on the cell measurement and neighbor cell frequency information, and the at least one indication.

[0358] Example 19: A method comprising:

[0359] At least one indication is received from at least one neighboring access node, the at least one indication indicating at least one of the following:

[0360] whether, for at least one frequency selective area identification FSAI or at least one multicast broadcast service MBS session at a neighboring access node among at least one neighboring access node, a reduced capability terminal device is supported,

[0361] for at least one type of reduced capability terminal device supported by at least one FSAI or at least one MBS session at a neighboring access node,

[0362] Common frequency resources CFR of at least one size for at least one FSAI or at least one MBS session at a neighboring access node,

[0363] At least one type of CFR currently in use by a neighboring access node for at least one FSAI or at least one MBS session;

[0364] Sending neighbor cell frequency information to a terminal device, the neighbor cell frequency information comprising: a mapping between at least one neighbor cell frequency and at least one FSAI of at least one MBS session, wherein the neighbor cell frequency is an operating frequency of a neighbor cell of a service cell provided by the apparatus; and

[0365] Sending at least one indication to a terminal device, the at least one indication indicating at least one of the following items for at least one neighboring cell provided by at least one neighboring access node:

[0366] Whether reduced-capability terminal devices are supported for at least one FSAI or at least one MBS session,

[0367] at least one type of reduced capability terminal device supported for at least one FSAI or at least one MBS session, or

[0368] • At least one size of CFR available for at least one FSAI or at least one MBS session.

[0369] Example 20: A method comprising:

[0370] receiving, from each of the one or more neighboring access nodes, at least one temporary mobile group identity (TMGI) associated with at least one multicast broadcast service (MBS) session ongoing at the neighboring access node, and receiving, for each of the at least one TMGI, at least one indication indicating at least one of:

[0371] Whether to support reduced-capability terminal devices for TMGI at adjacent access nodes,

[0372] for at least one type of reduced-capability terminal device supported by the TMGI at the neighboring access node, or

[0373] · CFR for at least one size of TMGI at a neighboring access node;

[0374] sending neighbor cell frequency information to a terminal device, the neighbor cell frequency information comprising: a mapping between at least one neighbor cell frequency and at least one FSAI of at least one MBS session, wherein the neighbor cell frequency is an operating frequency of a neighbor cell of a serving cell provided by the apparatus, and the neighbor cell frequency information is based on at least one TMGI, at least one indication, and a mapping between at least one TMGI of at least one MBS session and at least one FSAI; and

[0375] Sending at least one indication for at least one neighboring cell provided by one or more neighboring access nodes to a terminal device, wherein for the at least one neighboring cell, the at least one indication indicates at least one of the following items:

[0376] Whether reduced-capability terminal devices are supported for at least one FSAI or at least one MBS session,

[0377] at least one type of reduced capability terminal device supported for at least one FSAI or at least one MBS session, or

[0378] • At least one size of common frequency resources CFR available for at least one FSAI or at least one MBS session.

[0379] Example 21: A non-transitory computer-readable medium having instructions stored thereon that, when executed by a computing device, cause the computing device to perform:

[0380] receiving neighbor cell frequency information, the neighbor cell frequency information comprising: a mapping between at least one neighbor cell frequency and at least one frequency selection area identifier FSAI of at least one multicast broadcast service MBS session, wherein the neighbor cell frequency is an operating frequency of a neighbor cell of a serving cell of the apparatus;

[0381] Receiving at least one indication, the at least one indication indicating at least one of the following for at least one neighboring cell:

[0382] Whether reduced-capability terminal devices are supported for at least one FSAI or at least one MBS session,

[0383] at least one type of reduced capability terminal device supported for at least one FSAI or at least one MBS session, or

[0384] at least one size of common frequency resources CFR available for at least one FSAI or at least one MBS session; and

[0385] A cell reselection procedure is performed based on the cell measurement and neighbor cell frequency information, and the at least one indication.

[0386] Example 22: A non-transitory computer-readable medium having instructions stored thereon that, when executed by a computing device, cause the computing device to perform:

[0387] At least one indication is received from at least one neighboring access node, the at least one indication indicating at least one of the following:

[0388] whether, for at least one frequency selective area identification FSAI or at least one multicast broadcast service MBS session at a neighboring access node among at least one neighboring access node, a reduced capability terminal device is supported,

[0389] at least one type of reduced capability terminal device for at least one FSAI or at least one MBS session at a neighboring access node,

[0390] Common frequency resources CFR of at least one size for at least one FSAI or at least one MBS session at a neighboring access node,

[0391] At least one type of CFR currently in use by a neighboring access node for at least one FSAI or at least one MBS session;

[0392] Sending neighbor cell frequency information to a terminal device, the neighbor cell frequency information comprising: a mapping between at least one neighbor cell frequency and at least one FSAI of at least one MBS session, wherein the neighbor cell frequency is an operating frequency of a neighbor cell of a service cell provided by the apparatus; and

[0393] Sending at least one indication to a terminal device, the at least one indication indicating at least one of the following items based on at least one neighboring cell provided by at least one neighboring access node:

[0394] Whether reduced-capability terminal devices are supported for at least one FSAI or at least one MBS session,

[0395] at least one type of reduced capability terminal device supported for at least one FSAI or at least one MBS session, or

[0396] • At least one size of CFR available for at least one FSAI or at least one MBS session.

[0397] Example 23: A non-transitory computer-readable medium having instructions stored thereon that, when executed by a computing device, cause the computing device to perform:

[0398] receiving, from each of the one or more neighboring access nodes, at least one temporary mobile group identity (TMGI) associated with at least one multicast broadcast service (MBS) session ongoing at the neighboring access node, and receiving, for each of the at least one TMGI, at least one indication indicating at least one of:

[0399] Whether to support reduced-capability terminal devices for TMGI at adjacent access nodes,

[0400] for at least one reduced capability terminal device supported by the TMGI at the neighboring access node, or

[0401] · CFR for at least one size of TMGI at a neighboring access node;

[0402] sending neighbor cell frequency information to a terminal device, the neighbor cell frequency information comprising: a mapping between at least one neighbor cell frequency and at least one FSAI of at least one MBS session, wherein the neighbor cell frequency is an operating frequency of a neighbor cell of a serving cell provided by the apparatus, and the neighbor cell frequency information is based on at least one TMGI, at least one indication, and a mapping between at least one TMGI of at least one MBS session and at least one FSAI; and

[0403] Sending at least one indication for at least one neighboring cell provided by one or more neighboring access nodes to a terminal device, wherein for the at least one neighboring cell, the at least one indication indicates at least one of the following items:

[0404] Whether reduced-capability terminal devices are supported for at least one FSAI or at least one MBS session,

[0405] at least one type of reduced capability terminal device supported for at least one FSAI or at least one MBS session, or

[0406] • At least one size of common frequency resources CFR available for at least one FSAI or at least one MBS session.

[0407] Additional or alternative numbered example sets:

[0408] Example 1: An apparatus, comprising: at least one processor; and at least one memory, the at least one memory storing instructions, which, when executed by the at least one processor, causes the apparatus to at least perform: receiving neighbor cell frequency information, the neighbor cell frequency information comprising: a mapping between at least one neighbor cell frequency for at least one multicast broadcast service MBS session and at least one frequency selection area identifier FSAI, wherein the neighbor cell frequency is an operating frequency of a neighbor cell of a serving cell of the apparatus; receiving at least one indication for each at least one neighbor cell, the at least one indication indicating at least one of the following items:

[0409] whether reduced capability terminal devices are supported for at least one FSAI or at least one MBS session,

[0410] a terminal device that supports at least one type of reduced capability for at least one FSAI or at least one MBS session, or

[0411] at least one size of common frequency resources CFR that can be used for at least one FSAI or at least one MBS session; and

[0412] A cell reselection procedure is performed based on the cell measurement and neighbor cell frequency information, and the at least one indication.

[0413] Example 2. The apparatus of Example 1, wherein the neighbor cell frequency information and the at least one indication are received in a system information block 21 (SIB21) message.

[0414] Example 3. An apparatus according to any preceding example, wherein the apparatus is a reduced capability terminal device.

[0415] Example 4: An apparatus according to Example 3, wherein at least one indication indicates that a terminal device with reduced capabilities is supported for at least one FSAI or at least one MBS session without indicating at least one size of CFR that can be used for at least one FSAI or at least one MBS session; and at least one type of terminal device with reduced capabilities is supported for at least one FSAI or at least one MBS session; and wherein performing a cell reselection process includes: during the cell reselection process, giving priority to at least one adjacent cell frequency associated with at least one indication indicating that the terminal device with reduced capabilities is supported for at least one FSAI or at least one MBS session.

[0416] Example 5: An apparatus according to Example 3, wherein at least one indication indicates at least one size of CFR that can be used for at least one FSAI or at least one MBS session, and / or at least one type of reduced capability terminal device supported for at least one FSAI or at least one MBS session; and wherein performing a cell reselection process includes: in the cell reselection process, giving priority to at least one neighboring cell frequency associated with the size of the CFR supported by the reduced capability terminal device, and / or at least one neighboring cell frequency associated with the type of reduced capability terminal device corresponding to the reduced capability terminal device.

[0417] Example 6: An apparatus according to Example 1 or 2, wherein the apparatus is a non-reduced capability terminal device; and wherein executing a cell reselection process includes: during the cell reselection process, based on at least one indication and adjacent cell frequency information, giving priority to at least one adjacent cell frequency that cannot support a reduced capability terminal device.

[0418] Example 7: An apparatus according to any of the preceding examples, wherein at least one memory and instruction are configured to, together with at least one processor, cause the apparatus to execute: before receiving neighboring cell frequency information: receiving a service announcement for an MBS session, wherein the service announcement indicates at least one FSAI associated with the MBS session, or at least one frequency associated with the MBS session, wherein performing a cell reselection process is also based on the service announcement.

[0419] Example 8: The apparatus according to any preceding example, wherein the at least one memory and the instructions are configured to, together with the at least one processor, cause the apparatus to perform: operating in a radio resource control RRC idle or inactive state during execution of a cell reselection procedure.

[0420] Example 9: An apparatus comprising: at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus to at least perform: receiving at least one indication from at least one neighboring access node, the at least one indication indicating at least one of the following:

[0421] whether the reduced capability terminal device is supported for at least one frequency selective area identification FSAI or at least one multicast broadcast service MBS session at at least one neighboring access node,

[0422] a terminal device supported with at least one type of reduced capability for at least one FSAI or at least one MBS session at a neighboring access node,

[0423] at least one size of common frequency resources CFR used for at least one FSAI or at least one MBS session at a neighboring access node, or

[0424] At least one type of CFR currently being used by a neighboring access node for at least one FSAI or at least one MBS session;

[0425] Sending neighbor cell frequency information to a terminal device, the neighbor cell frequency information comprising: a mapping between at least one neighbor cell frequency for at least one MBS session and at least one FSAI, wherein the neighbor cell frequency is an operating frequency of a neighbor cell of a service cell provided by the apparatus; and

[0426] Sending at least one indication to a terminal device, the at least one indication indicating, for each at least one neighboring cell provided by at least one neighboring access node, at least one of the following:

[0427] whether reduced capability terminal devices are supported for at least one FSAI or at least one MBS session,

[0428] a terminal device that supports at least one type of reduced capability for at least one FSAI or at least one MBS session, or

[0429] • At least one size of CFR available for at least one FSAI or at least one MBS session.

[0430] Example 10: An apparatus according to Example 9, wherein at least one memory and instructions are configured to, together with at least one processor, cause the apparatus to execute: receiving a broadcast multicast broadcast service MBS session establishment request for an MBS session from a core network function, wherein the broadcast MBS session establishment request includes at least one FSAI associated with the MBS session.

[0431] Example 11: An apparatus according to Example 10, wherein at least one memory and instruction are configured to, together with at least one processor, cause the apparatus to execute: receiving configuration information from an operation, supervision and management (OAM) entity, wherein the configuration information includes at least one indication indicating that: at least one FSAI associated with the MBS session is defined for a terminal device with reduced capabilities; and based on the configuration information, triggering transmission of the MBS session within a CFR defined for the terminal device with reduced capabilities.

[0432] Example 12: The apparatus of any one of Examples 9 to 11, wherein the at least one memory and the instructions are configured to, with the at least one processor, cause the apparatus to execute: sending at least one indication to at least one neighboring access node, the at least one indication indicating at least one of the following:

[0433] whether reduced capability terminal equipment is supported for at least one FSAI or at least one MBS session at the device,

[0434] a terminal device that supports at least one type of reduced capability for at least one FSAI or at least one MBS session at the device, or

[0435] at least one size of CFR used for at least one FSAI or at least one MBS session at the device, or

[0436] • The type of CFR currently being used by the device for at least one FSAI or at least one MBS session.

[0437] Example 13: An apparatus comprising: at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus to at least perform: receiving, from each of one or more neighboring access nodes, at least one temporary mobile group identifier (TMGI) associated with at least one multicast broadcast service (MBS) session ongoing at the neighboring access node, and for each of the at least one TMGI, receiving at least one indication indicating at least one of the following:

[0438] whether reduced-capability terminal devices are supported for TMGI at the neighboring access node,

[0439] a terminal device that supports at least one type of reduced capability for TMGI at a neighboring access node, or

[0440] CFR of at least one size used for TMGI at neighboring access nodes;

[0441] Sending neighbor cell frequency information to a terminal device, the neighbor cell frequency information comprising: a mapping between at least one neighbor cell frequency for at least one MBS session and at least one FSAI, wherein the neighbor cell frequency is an operating frequency of a neighbor cell of a serving cell provided by the apparatus, and the neighbor cell frequency information is based on at least one TMGI, at least one indication, and a mapping between at least one TMGI for at least one MBS session and at least one FSAI; and sending at least one indication for at least one neighbor cell provided by one or more neighboring access nodes to the terminal device, wherein for each at least one neighbor cell, the at least one indication indicates at least one of the following items:

[0442] whether reduced capability terminal devices are supported for at least one FSAI or at least one MBS session,

[0443] a terminal device that supports at least one type of reduced capability for at least one FSAI or at least one MBS session, or

[0444] • At least one size of common frequency resources CFR available for at least one FSAI or at least one MBS session.

[0445] Example 14: The apparatus of Example 13, wherein the at least one memory and the instructions are configured to, with the at least one processor, cause the apparatus to execute: sending at least one TMGI associated with at least one MBS session ongoing at the apparatus to each of the one or more neighboring access nodes, and for each of the at least one TMGI associated with at least one MBS session ongoing at the apparatus, sending at least one indication indicating at least one of the following:

[0446] whether reduced-capability terminal equipment is supported for the TMGI at the device,

[0447] a reduced-capability terminal device that supports at least one type of TMGI for use at the device, or

[0448] • CFR of at least one size of TMGI used at the device.

[0449] Example 15: An apparatus according to Example 13 or 14, wherein at least one memory and instruction are configured to, together with at least one processor, cause the apparatus to perform: before transmission of neighboring cell frequency information: receiving a broadcast MBS session establishment request for an MBS session from a core network function, wherein the broadcast MBS session establishment request includes: at least one FSAI associated with the MBS session; and determining a mapping between at least one TMGI and at least one FSAI for at least one MBS session based on the broadcast MBS session establishment request and at least one TMGI, and at least one indication received from one or more neighboring access nodes.

[0450] Example 16: An apparatus according to Example 15, wherein at least one memory and instructions are configured to, together with at least one processor, cause the apparatus to perform: receiving configuration information from an operation, manipulation, and management (OAM) entity, wherein the configuration information includes at least one indication indicating that: at least one FSAI associated with an MBS session supported by the apparatus is defined for a reduced capability terminal device; and based on the configuration information, triggering transmission of the MBS session within a CFR defined for the reduced capability terminal device.

[0451] Example 17: An apparatus according to any one of Examples 9 to 16, wherein the neighbor cell frequency information and the at least one indication are sent to the terminal device in a system information block 21 (SIB21) message.

[0452] Example 18: A method, comprising: receiving neighbor cell frequency information, the neighbor cell frequency information comprising: a mapping between at least one neighbor cell frequency for at least one multicast broadcast service MBS session and at least one frequency selection area identifier FSAI, wherein the neighbor cell frequency is an operating frequency of a neighbor cell of a serving cell of the apparatus; and receiving, for each at least one neighbor cell, at least one indication indicating at least one of the following items:

[0453] whether reduced capability terminal devices are supported for at least one FSAI or at least one MBS session,

[0454] a terminal device that supports at least one type of reduced capability for at least one FSAI or at least one MBS session, or

[0455] at least one size of common frequency resources CFR available for at least one FSAI or at least one MBS session; and

[0456] A cell reselection procedure is performed based on the cell measurement and neighbor cell frequency information, and the at least one indication.

[0457] Example 19: A method comprising:

[0458] At least one indication is received from at least one neighboring access node, the at least one indication indicating at least one of the following:

[0459] whether the reduced capability terminal device is supported for at least one frequency selective area identification FSAI or at least one multicast broadcast service MBS session at at least one neighboring access node,

[0460] a terminal device supported with at least one type of reduced capability for at least one FSAI or at least one MBS session at a neighboring access node,

[0461] at least one size of common frequency resources CFR used for at least one FSAI or at least one MBS session at a neighboring access node,

[0462] At least one type of CFR currently being used by a neighboring access node for at least one FSAI or at least one MBS session;

[0463] Sending neighbor cell frequency information to a terminal device, the neighbor cell frequency information comprising: a mapping between at least one neighbor cell frequency for at least one MBS session and at least one FSAI, wherein the neighbor cell frequency is an operating frequency of a neighbor cell of a serving cell provided by the apparatus; and for each at least one neighbor cell provided by at least one neighboring access node, sending at least one indication to the terminal device, the at least one indication indicating at least one of the following items:

[0464] whether reduced capability terminal devices are supported for at least one FSAI or at least one MBS session,

[0465] a terminal device that supports at least one type of reduced capability for at least one FSAI or at least one MBS session, or

[0466] • At least one size of CFR available for at least one FSAI or at least one MBS session.

[0467] Example 20: A method comprising: receiving, from each of one or more neighboring access nodes, at least one temporary mobile group identity (TMGI) associated with at least one multicast broadcast service (MBS) session ongoing at the neighboring access node, and for each of the at least one TMGI, receiving at least one indication indicating at least one of the following:

[0468] whether reduced-capability terminal devices are supported for TMGI at the neighboring access node,

[0469] a terminal device that supports at least one type of reduced capability for TMGI at a neighboring access node, or

[0470] CFR of at least one size used for TMGI at neighboring access nodes;

[0471] Sending neighbor cell frequency information to a terminal device, the neighbor cell frequency information comprising: a mapping between at least one neighbor cell frequency for at least one MBS session and at least one FSAI, wherein the neighbor cell frequency is an operating frequency of a neighbor cell of a serving cell provided by the apparatus, and the neighbor cell frequency information is based on at least one TMGI, at least one indication, and a mapping between at least one TMGI for at least one MBS session and at least one FSAI; and sending at least one indication for at least one neighbor cell provided by one or more neighboring access nodes to the terminal device, wherein for each at least one neighbor cell, the at least one indication indicates at least one of the following items:

[0472] whether reduced capability terminal devices are supported for at least one FSAI or at least one MBS session,

[0473] a terminal device that supports at least one type of reduced capability for at least one FSAI or at least one MBS session, or

[0474] • At least one size of common frequency resources CFR available for at least one FSAI or at least one MBS session.

[0475] Example 21: A non-transitory computer-readable medium having instructions stored thereon, which, when executed by a computing device, cause the computing device to perform: receiving neighbor cell frequency information, the neighbor cell frequency information comprising: a mapping between at least one neighbor cell frequency for at least one multicast broadcast service MBS session and at least one frequency selection area identifier FSAI, wherein the neighbor cell frequency is an operating frequency of a neighbor cell of a serving cell of the apparatus; for each at least one neighbor cell, receiving at least one indication, the at least one indication indicating at least one of the following items:

[0476] whether reduced capability terminal devices are supported for at least one FSAI or at least one MBS session,

[0477] a terminal device that supports at least one type of reduced capability for at least one FSAI or at least one MBS session, or

[0478] at least one size of common frequency resources CFR available for at least one FSAI or at least one MBS session; and

[0479] A cell reselection procedure is performed based on the cell measurement and neighbor cell frequency information, and the at least one indication.

[0480] Example 22: A non-transitory computer-readable medium having instructions stored thereon, which, when executed by a computing device, cause the computing device to perform: receiving at least one indication from at least one neighboring access node, the at least one indication indicating at least one of the following:

[0481] whether the reduced capability terminal device is supported for at least one frequency selective area identification FSAI or at least one multicast broadcast service MBS session at at least one neighboring access node,

[0482] a terminal device supported with at least one type of reduced capability for at least one FSAI or at least one MBS session at a neighboring access node,

[0483] at least one size of common frequency resources CFR used for at least one FSAI or at least one MBS session at a neighboring access node,

[0484] At least one type of CFR currently being used by a neighboring access node for at least one FSAI or at least one MBS session;

[0485] Sending neighbor cell frequency information to a terminal device, the neighbor cell frequency information comprising: a mapping between at least one neighbor cell frequency for at least one MBS session and at least one FSAI, wherein the neighbor cell frequency is an operating frequency of a neighbor cell of a serving cell provided by the apparatus; and for each at least one neighbor cell provided by at least one neighboring access node, sending at least one indication to the terminal device, the at least one indication indicating at least one of the following items:

[0486] whether reduced capability terminal devices are supported for at least one FSAI or at least one MBS session,

[0487] a terminal device that supports at least one type of reduced capability for at least one FSAI or at least one MBS session, or

[0488] • At least one size of CFR available for at least one FSAI or at least one MBS session.

[0489] Example 23: A non-transitory computer-readable medium having instructions stored thereon, which, when executed by a computing device, cause the computing device to perform: receiving, from each of one or more neighboring access nodes, at least one temporary mobile group identity (TMGI) associated with at least one multicast broadcast service (MBS) session ongoing at the neighboring access node, and for each of the at least one TMGI, receiving at least one indication indicating at least one of the following:

[0490] whether reduced-capability terminal devices are supported for TMGI at the neighboring access node,

[0491] a terminal device that supports at least one type of reduced capability for TMGI at a neighboring access node, or

[0492] CFR of at least one size used for TMGI at neighboring access nodes;

[0493] Sending neighbor cell frequency information to a terminal device, the neighbor cell frequency information comprising: a mapping between at least one neighbor cell frequency for at least one MBS session and at least one FSAI, wherein the neighbor cell frequency is an operating frequency of a neighbor cell of a serving cell provided by the apparatus, and the neighbor cell frequency information is based on at least one TMGI, at least one indication, and a mapping between at least one TMGI for at least one MBS session and at least one FSAI; and sending at least one indication for at least one neighbor cell provided by one or more neighboring access nodes to the terminal device, wherein for each at least one neighbor cell, the at least one indication indicates at least one of the following items:

[0494] whether reduced capability terminal devices are supported for at least one FSAI or at least one MBS session,

[0495] a terminal device that supports at least one type of reduced capability for at least one FSAI or at least one MBS session, or

[0496] • At least one size of common frequency resources CFR available for at least one FSAI or at least one MBS session.

[0497] References to an embodiment or embodiments throughout the specification mean that the specific features, structures or characteristics described in conjunction with the embodiment are included in at least one embodiment of the present technical solution. Therefore, the phrases "in one embodiment" or "in an embodiment" appearing in various places throughout the specification do not necessarily all refer to the same embodiment.

[0498] As used herein, for convenience, multiple projects, structural elements, constituent elements, and / or materials can be presented in a public list. However, these lists should be interpreted as if each member of the list is individually identified as a separate and unique member. Therefore, unless otherwise indicated, the individual members of such a list should not be interpreted as the de facto equivalents of any other members of the same list based only on the presentation of the individual members of such a list in a public group. In addition, various embodiments and examples of the present technical solution and alternatives to its various components may be cited herein. It should be understood that such embodiments, examples and alternatives should not be interpreted as de facto equivalents to each other, but should be regarded as separate and autonomous representations of the present technical solution.

[0499] Even though the embodiments have been described above with reference to the examples according to the accompanying drawings, it is obvious that the embodiments are not limited thereto but can be modified in several ways within the scope of the appended claims. Therefore, all words and expressions should be interpreted broadly and they are intended to illustrate rather than limit the embodiments. It will be obvious to those skilled in the art that, with the advancement of technology, the concepts of the present invention can be implemented in various ways. In addition, it will be obvious to those skilled in the art that the described embodiments can, but not necessarily, be combined with other embodiments in various ways.

[0500] Industrial Applicability

[0501] At least some embodiments find industrial application in wireless communications.

Claims

1. A device for communication, comprising: at least one processor; as well as at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus to at least perform: Receiving a service announcement of a multicast broadcast service MBS; receiving at least one indication in the service announcement and / or in at least one message following the service announcement, the at least one indication indicating that: all or at least some of the reduced-capability terminal devices for the MBS are supported; and Based on the cell measurement and the at least one indication, a cell reselection procedure is performed.

2. The device according to claim 1, wherein: The service announcement comprises: at least one frequency selection area identifier FSAI associated with the MBS and the at least one indication, the at least one indication indicating that the at least one FSAI is defined for a terminal device with reduced capability, and / or The service announcement includes: at least one frequency associated with the MBS and the at least one indication indicating that the at least one frequency is defined for a reduced capability terminal device, Performing the cell reselection procedure is also based on the at least one FSAI, and / or the at least one frequency.

3. The apparatus of claim 2, wherein the apparatus is a reduced capability terminal device; and wherein performing the cell reselection procedure comprises: In the cell reselection procedure, frequencies associated with the at least one FSAI or the at least one frequency indicated as defined for a reduced capability terminal device are prioritized.

4. The apparatus of claim 3, wherein the service announcement further comprises one or more FSAIs, or one or more frequencies, without any indication that the one or more FSAIs, or the one or more frequencies are defined for a reduced capability terminal device; wherein the prioritization comprises: During the cell reselection process, priority is given to the frequencies associated with the at least one FSAI or the at least one frequency that is indicated as being defined for a terminal device with reduced capabilities, at least relative to the frequencies associated with the one or more FSAIs or the one or more frequencies that are not indicated as being defined for a terminal device with reduced capabilities.

5. The apparatus of claim 2, wherein the apparatus is a non-reduced capability terminal device, the service announcement further comprises one or more FSAIs, or one or more frequencies, without any indication that the one or more FSAIs, or the one or more frequencies are defined for reduced capability terminal devices; and wherein performing the cell reselection procedure comprises: During the cell reselection process, frequencies associated with at least one FSAI, or at least one frequency, that is not indicated as being defined for a terminal device with reduced capabilities are given priority over frequencies associated with the one or more FSAIs, or the one or more frequencies, that are indicated as being defined for a terminal device with reduced capabilities.

6. The apparatus of claim 2, wherein for at least one of the at least one FSAI or the at least one frequency, the service announcement further comprises: The information about at least one bandwidth restriction condition is indicated as the at least one FSAI or at least one frequency defined for the reduced capability terminal device complying with the at least one bandwidth restriction condition.

7. The apparatus of claim 6, wherein the at least one bandwidth limitation condition comprises: Conditions on bandwidth size, and / or conditions on types of terminal devices with reduced capabilities.

8. The apparatus according to claim 6 or 7, wherein the apparatus is a reduced capability terminal device; and wherein performing the cell reselection procedure comprises: determining, for the at least one frequency or the at least one FSAI associated with the at least one bandwidth restriction condition, whether the reduced capability terminal device satisfies the at least one bandwidth restriction condition; as well as In the cell reselection process, frequencies associated with at least one FSAI or at least one frequency for which the reduced capability terminal device satisfies the at least one bandwidth restriction condition are prioritized.

9. The apparatus of claim 8, wherein the service announcement comprises one or more FSAIs or one or more frequencies without any indication that the one or more FSAIs or the one or more frequencies are defined for a reduced capability terminal device, the prioritization comprising: During the cell reselection process, priority is given to the frequencies associated with the at least one FSAI or the at least one frequency that satisfies the at least one bandwidth restriction condition for the terminal device with reduced capability, at least relative to the frequencies associated with the one or more FSAIs or the one or more frequencies that are not indicated as being defined for the terminal device with reduced capability.

10. The apparatus according to any one of claims 2 to 9, wherein the service announcement comprises the at least one FSAI and the at least one indication indicating that the at least one FSAI is defined for a reduced capability terminal device, and the at least one memory and the instructions are configured to, together with the at least one processor, cause the apparatus to perform: receiving, in the at least one message following the service announcement, a mapping between the at least one FSAI defined in the service announcement and at least one frequency; and Further based on the mapping, the cell reselection process is performed.

11. The apparatus of claim 1 , wherein the at least one memory and the instructions are configured to, together with the at least one processor, cause the apparatus to further execute: Receive neighboring cell frequency information, where the neighboring cell frequency information includes: a mapping between at least one neighbor cell frequency for at least one MBS session of the MBS and at least one FSAI, wherein the neighbor cell frequency is an operating frequency of a neighbor cell of a serving cell of the apparatus, and performing the cell reselection is further based on the neighbor cell frequency information, The at least one message following the service announcement comprises the at least one indication indicating, for each at least one neighboring cell, support for the at least one FSAI or the at least one MBS session, support for all or at least some of the reduced capability terminal devices for the MBS.

12. The apparatus of claim 11, wherein for each at least one neighboring cell, the at least one indication indicates at least one of the following: whether reduced capability terminal devices are supported for the at least one FSAI or the at least one MBS session, a terminal device that supports at least one type of reduced capability for the at least one FSAI or the at least one MBS session, or • At least one size of common frequency resources CFR that can be used for the at least one FSAI or the at least one MBS session.

13. The apparatus according to claim 11 or 12, wherein the apparatus is a reduced capability terminal device.

14. The apparatus of claim 13, wherein the at least one indication indicates that a reduced-capability terminal device is supported for the at least one FSAI or the at least one MBS session without indicating the at least one size of the CFR that can be used for the at least one FSAI or the at least one MBS session; and the at least one type of reduced-capability terminal device is supported for the at least one FSAI or the at least one MBS session; wherein performing the cell reselection procedure comprises: In the cell reselection procedure, at least one neighbor cell frequency associated with the at least one indication indicating that a reduced capability terminal device is supported for the at least one FSAI or the at least one MBS session is prioritized.

15. The apparatus according to claim 13, wherein the at least one indication specifies the at least one size of the CFR that can be used for the at least one FSAI or the at least one MBS session, and / or the terminal devices that are supported for the at least one type of reduced capability for the at least one FSAI or the at least one MBS session; and The cell reselection process includes: In the cell reselection process, priority is given to at least one neighbor cell frequency associated with a CFR size supported by the reduced capability terminal device and / or at least one neighbor cell frequency associated with a type of reduced capability terminal device corresponding to the reduced capability terminal device.

16. The apparatus according to claim 11 or 12, wherein the apparatus is a non-reduced capability terminal device; and wherein performing the cell reselection procedure comprises: In the cell reselection process, based on the at least one indication and the neighboring cell frequency information, at least one neighboring cell frequency that cannot support the terminal device with reduced capability is prioritized.

17. The apparatus according to any preceding claim, wherein the service announcement indicates: at least one FSAI associated with the MBS session, or at least one frequency associated with the MBS session, wherein performing the cell reselection procedure is further based on the service announcement.

18. An apparatus as claimed in any preceding claim, wherein the at least one message is, or comprises, a System Information Block 21 (SIB21) message.

19. An apparatus according to any preceding claim, wherein the at least one memory and the instructions are configured to, with the at least one processor, cause the apparatus to perform: During the cell reselection process, the cell is operated in a radio resource control RRC idle or inactive state.

20. A method for communication, comprising: Receiving a service announcement of a multicast broadcast service MBS; receiving at least one indication in the service announcement and / or in at least one message following the service announcement, the at least one indication indicating that: all or at least some of the reduced-capability terminal devices for the MBS are supported; and Based on the cell measurement and the at least one indication, a cell reselection procedure is performed.

21. A non-transitory computer-readable medium having instructions stored thereon, which, when executed by a computing device, cause the computing device to perform: Receiving a service announcement of a multicast broadcast service MBS; receiving at least one indication in the service announcement and / or in at least one message following the service announcement, the at least one indication indicating that: all or at least some of the reduced-capability terminal devices for the MBS are supported; and Based on the cell measurement and the at least one indication, a cell reselection procedure is performed.

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