WO2024109165A1

WO2024109165A1 - Broadcast services in ntn

Info

Publication number: WO2024109165A1
Application number: PCT/CN2023/111542
Authority: WO
Inventors: Min Xu
Original assignee: Lenovo (Beijing) Limited
Priority date: 2023-08-07
Filing date: 2023-08-07
Publication date: 2024-05-30

Abstract

Various aspects of the present disclosure relate to devices and methods for broadcast services in a non-terrestrial network (NTN). In an aspect, a UE receives, from a base station, a first configuration for a broadcast service in an NTN. The UE performs broadcast service management based on the first configuration. In this way, the UE in an NTN cell can efficiently determine whether to receive a broadcast service, so as to avoid unnecessary cell reselection and to enable/disable MCCH monitoring when necessary.

Description

BROADCAST SERVICES IN NTN

FIELD

The present disclosure relates to wireless communications, and more specifically to methods and apparatuses for providing a broadcast service in a non-terrestrial network (NTN) .

BACKGROUND

A wireless communications system may include one or multiple network communication devices, such as base stations, which may be otherwise known as an eNodeB (eNB) , a next-generation NodeB (gNB) , or other suitable terminology. Each network communication devices, such as a base station may support wireless communications for one or multiple user communication devices, which may be otherwise known as user equipment (UE) , or other suitable terminology. The wireless communications system may support wireless communications with one or multiple user communication devices by utilizing resources of the wireless communication system (e.g., time resources (e.g., symbols, slots, subframes, frames, or the like) or frequency resources (e.g., subcarriers, carriers) . Additionally, the wireless communications system may support wireless communications across various radio access technologies including third generation (3G) radio access technology, fourth generation (4G) radio access technology, fifth generation (5G) radio access technology, among other suitable radio access technologies beyond 5G (e.g., sixth generation (6G) ) .

In the 3rd Generation Partnership Project (3GPP) Rel-17, the feature of Multicast and Broadcast Service (MBS) was introduced for New Radio (NR) to provide Point to Multipoint (PTM) services with substantial improvements regarding efficient resources usage and user experience. In 3GPP Rel-17, the feature of NTN was also specified to support Radio Access Network (RAN) deployment over satellite. NTN refers to a network, or a segment of networks using Radio Frequency (RF) resources on board a satellite. Study on providing a broadcast service in an NTN is required.

SUMMARY

The present disclosure relates to methods and apparatuses for providing a broadcast service in an NTN. By receiving a first configuration for a broadcast service in an NTN and performing broadcast service management based on the first configuration, a UE in an NTN cell can efficiently determine whether to receive a broadcast service, so as to avoid unnecessary cell reselection and to enable/disable MBS Control Channel (MCCH) monitoring when necessary.

In an aspect, some implementations of the methods and apparatuses described herein may include: receiving, from a base station, a first configuration for a broadcast service in an NTN; and performing broadcast service management based on the first configuration.

In some implementations of the methods and apparatuses described herein, the first configuration comprises configuration information for the user equipment to determine whether to receive the broadcast service from the base station.

In some implementations of the methods and apparatuses described herein, performing the broadcast service management comprises: in the case that the user equipment determines, based on the configuration information, to receive the broadcast service, receiving the broadcast service from the base station; and monitoring a Multicast and Broadcast Services (MBS) Control Channel (MCCH) corresponding to the broadcast service.

In some implementations of the methods and apparatuses described herein, performing the broadcast service management comprises: in the case that the user equipment determines, based on the configuration information, not to receive the broadcast service, refraining from receiving the broadcast service from the base station; and refraining from monitoring an MCCH corresponding to the broadcast service.

In some implementations of the methods and apparatuses described herein, the configuration information comprises a parameter associated with an area of the broadcast service, and determining whether to receive the broadcast service comprises: determining whether a criterion indicated by the parameter is fulfilled.

In some implementations of the methods and apparatuses described herein, the parameter comprises one of the following: a reference location and a radius; or more than one location.

In some implementations of the methods and apparatuses described herein, the criterion comprises the user equipment being in the area indicated by the parameter.

In some implementations of the methods and apparatuses described herein, the parameter comprises one of the following: an identity of a beam in a serving cell of the NTN; an identity of an RAN notification area; an angle threshold for an angle between the user equipment and a satellite that provides the serving cell; a first time threshold for a propagation delay between the user equipment and the satellite or the base station; or a second time threshold for a timing advance between the user equipment and the satellite or the base station.

In some implementations of the methods and apparatuses described herein, the criterion comprises one of the following: the user equipment selects the beam indicated by the identity of the beam; the user equipment is in the RAN notification area; the angle between the user equipment and the satellite is smaller or larger than the angle threshold; the propagation delay is smaller or larger than the first time threshold; or the timing advance is smaller or larger than the second time threshold.

In some implementations of the methods and apparatuses described herein, the configuration information comprises an indication of whether the user equipment receives the broadcast service from the base station, and determining whether to receive the broadcast service comprises: determining whether the indication indicates the user equipment to receive the broadcast service.

In some implementations of the methods and apparatuses described herein, the first configuration further comprises a validity duration for the indication.

In some implementations of the methods and apparatuses described herein, the first configuration comprises a stop serving time or a feeder link switch time of at least one neighbor cell in the NTN that supports the broadcast service.

Some implementations of the methods and apparatuses described herein may further include: determining a frequency priority for the broadcast service based on the stop serving time or the feeder link switch time of the at least one neighbor cell.

In some implementations of the methods and apparatuses described herein, determining the frequency priority for the broadcast service comprises: restricting to consider a frequency to be the highest priority during a broadcast session of the broadcast service, in the case that a condition is fulfilled.

In some implementations of the methods and apparatuses described herein, the condition comprises one of the following: the at least one neighbor cell using the frequency is approaching the stop serving time or the feeder link switch time; remaining time before the stop serving time or the feeder link switch time is less than a threshold; or remaining time before the stop serving time or the feeder link switch time is less than an expected reception duration of the broadcast service at the user equipment.

Some implementations of the methods and apparatuses described herein may further include: applying an offset to a parameter value for a cell reselection based on the stop serving time or the feeder link switch time.

In some implementations of the methods and apparatuses described herein, applying the offset to the parameter value for the cell reselection comprises at least one of the following: applying a reference signal received power (RSRP) offset to an RSRP threshold for the cell reselection; applying a reference signal received quality (RSRQ) offset to an RSRQ threshold for the cell reselection; or applying a time offset to a time threshold for the cell reselection.

In some implementations of the methods and apparatuses described herein, the cell reselection comprises one of the following: a non-equal inter-frequency cell reselection; an inter-radio access technology (inter-RAT) cell reselection; an intra-frequency cell reselection; or an equal priority inter-frequency cell reselection.

In some implementations of the methods and apparatuses described herein, the offset is associated with remaining time before the stop serving time or the feeder link switch time.

Some implementations of the methods and apparatuses described herein may further include: receiving the stop serving time or the feeder link switch time in one of the following: a system information block 2 (SIB2) associated with the at least one neighbor cell; an SIB19 associated with the at least one neighbor cell; an SIB20 associated with an MBS configuration for broadcast or part of the MBS configuration for broadcast; an SIB21 associated with a frequency or a frequency selection area identity (FSAI) ; or dedicated signaling.

In some implementations of the methods and apparatuses described herein, the first configuration comprises an indication of acquiring an MCCH configuration in the case that the user equipment does not receive an MCCH change notification at an MCCH modification period boundary.

Some implementations of the methods and apparatuses described herein may further include: acquiring an MCCH configuration on one of the following conditions: after a global navigation satellite system (GNSS) measurement is complete; after a GNSS measurement is complete, in the case that a corresponding measurement duration covers the MCCH modification period boundary; after GNSS measurements is complete, in the case that the MCCH change notification is received in a network response for GNSS result reporting; after acquiring SIB19 is complete; after acquiring SIB19 is complete, in the case that a corresponding acquiring duration covers the MCCH modification period boundary; or after acquiring SIB19 is complete, in the case that the MCCH change notification is received in the acquired SIB19.

In another aspect, some implementations of the methods and apparatuses described herein may include: determining a first configuration for a broadcast service in an NTN; and transmitting to a user equipment, via the transceiver, the first configuration.

In some implementations of the methods and apparatuses described herein, the configuration information comprises a parameter associated with an area of the broadcast service.

In some implementations of the methods and apparatuses described herein, the configuration information comprises an indication of whether the user equipment receives the broadcast service from the base station.

Some implementations of the methods and apparatuses described herein may further include: transmitting the stop serving time or the feeder link switch time in one of the following: an SIB2 associated with the at least one neighbor cell; an SIB19 associated with the at least one neighbor cell; an SIB20 associated with an MBS configuration for broadcast or part of the MBS configuration for broadcast; an SIB21 associated with a frequency or a frequency selection area identity (FSAI) ; or dedicated signaling.

In some implementations of the methods and apparatuses described herein, the indication indicates the user equipment to acquire an MCCH configuration on one of the following conditions: after a GNSS measurement is complete; after a GNSS measurement is complete, in the case that a corresponding measurement duration covers the MCCH modification period boundary; after GNSS measurements is complete, in the case that the MCCH change notification is received in a network response for GNSS result reporting; after acquiring SIB19 is complete; after acquiring SIB19 is complete, in the case that a corresponding acquiring duration covers the MCCH modification period boundary; or after acquiring SIB19 is complete, in the case that the MCCH change notification is received in the acquired SIB19.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A illustrates an example of a wireless communications system that supports a broadcast service in an NTN in accordance with aspects of the present disclosure.

FIG. 1B illustrates an example diagram of relation between an MBS broadcast service area and cell coverage in the terrestrial network (TN) and NTN.

FIG. 2 illustrates an example signaling chart of an example process that supports a broadcast service in an NTN in accordance with aspects of the present disclosure.

FIG. 3 illustrates an example procedure that supports a broadcast service in an NTN in accordance with aspects of the present disclosure.

FIG. 4 illustrates an example of a device that supports a broadcast service in an NTN in accordance with aspects of the present disclosure.

FIG. 5 illustrates an example of a processor that supports a broadcast service in an NTN in accordance with aspects of the present disclosure.

FIG. 6 illustrates a flowchart of a method that supports a broadcast service in an NTN in accordance with aspects of the present disclosure.

FIG. 7 illustrates a flowchart of another method that supports a broadcast service in an NTN in accordance with aspects of the present disclosure.

DETAILED DESCRIPTION

Principles of the present disclosure will now be described with reference to some embodiments. It is to be understood that these embodiments are described only for the purpose of illustration and help those skilled in the art to understand and implement the present disclosure, without suggesting any limitation as to the scope of the disclosure. The disclosure described herein may be implemented in various manners other than the ones described below.

In the following description and claims, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skills in the art to which this disclosure belongs.

References in the present disclosure to “one embodiment, ” “an example embodiment, ” “an embodiment, ” “some embodiments, ” and the like indicate that the embodiment (s) described may include a particular feature, structure, or characteristic, but it is not necessary that every embodiment includes the particular feature, structure, or characteristic. Moreover, such phrases do not necessarily refer to the same embodiment (s) . Further, when a particular feature, structure, or characteristic is described in connection with an embodiment, it is submitted that it is within the knowledge of one skilled in the art to affect such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described.

It shall be understood that although the terms “first” and “second” or the like may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another element. For example, a first element could also be termed as a second element, and similarly, a second element could also be termed as a first element, without departing from the scope of embodiments. As used herein, the term “and/or” includes any and all combinations of one or more of the listed terms.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments. As used herein, the singular forms “a” , “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” , “comprising” , “has” , “having” , “includes” and/or “including” , when used herein, specify the presence of stated features, elements, and/or components etc., but do not preclude the presence or addition of one or more other features, elements, components and/or combinations thereof. As used herein, “at least one of the following: <a list of two or more elements>” and “at least one of <a list of two or more elements>” and similar wording, where the list of two or more elements are joined 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 the elements.

In 3GPP Rel-17, the feature of NTN was specified to support RAN deployment over satellite. The satellite in NTN can be a Geostationary Earth Orbiting (GEO) satellite with fixed location to the earth, or a Low Earth Orbiting (LEO) satellite orbiting around the earth.

The NTN with large coverage is well suited to support MBS in providing services to more UEs with higher resource efficiency. Therefore, in the latest 3GPP RAN workshop for Rel-19 scopes, it is proposed to support MBS in Rel-19 NTN and study the potential enhancements. For the MBS broadcast services in NTN, the following objective was proposed:

While the features enabling the provision of MBS service have been defined in Rel-17, some technical issues brought by NTN characteristics need to be addressed, including e.g., cell coverage up to thousands of kilometers and cell change due to satellite movement. In the following description, the terms “broadcast service” and “MBS broadcast service” may be used interchangeably.

One of the potential issues may relate to providing MBS broadcast service in a geographical area smaller than an NTN cell. For MBS broadcast services, the same service and the same specific content data are provided simultaneously to all UEs in a geographical area, and all UEs in the MBS broadcast service area are authorized to receive the data. To ensure that UE in an MBS broadcast service area is aware that it is authorized to receive the corresponding services, the UE can process the serviceArea element received in the User Service Description (USD) from network, wherein the serviceArea element declares the one or more service areas over which a corresponding service is provided and is designated by the Service Area Identity (SAI) . The SAI is frequency agnostic and can be mapped onto one or more cells as defined in 3GPP TS 36.443.

To ensure that UE out of the MBS broadcast service area is aware that it is not authorized to receive the corresponding services, according to 3GPP TS 38.331, it is up to UE implementation to use the cell/tracking area list in the USD to avoid acquiring the MCCH when the UE is outside the MBS broadcast service area.

From the above description and analysis, it is observed that in Rel-17 MBS designed for TN, UE can simply judge whether it is in an MBS broadcast service area by its serving cell and the corresponding MBS broadcast configuration it receives. This mechanism is workable based on the assumption that an MBS broadcast service area is larger than TN cell coverage so that the service area can be mapped to one or more TN cells.

However, the diameter of an NTN cell (i.e. satellite beam footprint size) is up to 1000km for LEO and 3500km for GEO, which could be much larger than an MBS broadcast service area. Meanwhile, an NTN cell may cross country border on one side of which providing an MBS broadcast service is not allowed or authorized. As a result, a UE may not be automatically authorized to receive an MBS broadcast service by the serving NTN cell it is in, i.e., not all UE within the same NTN cell is authorized to receive the same MBS broadcast service.

In such case, solutions are needed to ensure that UE served by an NTN cell in the service area of an MBS broadcast service can receive or process the corresponding service, or to ensure that UE served by an NTN cell but NOT in the service area of an MBS broadcast service cannot receive or process the corresponding service.

Another potential issue may relate to handling the frequency priority and cell reselection rules dedicated for an MBS broadcast service in NTN. In Rel-17 MBS, to guarantee broadcast service continuity in RRC_IDLE and RRC_INACTIVE state, frequency priority handling was enhanced for cell reselection. If the MBS broadcast capable UE is receiving or interested to receive an MBS broadcast service (s) and can only receive this MBS broadcast service (s) by camping on a frequency on which it is provided, the UE may consider that frequency to be the highest priority during the MBS broadcast session.

In TN such priority handling is reasonable as the TN cells are sustainably valid on earth. On the contrary, an NTN cell generated by NGSO (e.g., LEO) satellite has a validity duration ending at its service stop time t-Service (or its feeder link switch time t-FeederLinkSwitch) . It is meaningless to prioritize a frequency for MBS broadcast during cell reselection if a neighbour NTN cell on that frequency is approaching t-Service or t-FeederLinkSwitch, or to reselect to a neighbour NTN cell on that frequency approaching or t-FeederLinkSwitch.

Meanwhile, although UE may determine whether an MBS broadcast session is ongoing from the start and stop time indicated in the USD, it cannot determine whether the session is going to stop due to approaching t-Service or t-FeederLinkSwitch in a neighbour NTN cell, e.g., it is possible that the service stop time in USD indicates ongoing service but a neighbour NTN cell providing that service is about to expire.

In such case, solutions are needed for frequency priority handling and cell reselection dedicated for an MBS broadcast service in NTN, to restrict UE from prioritizing an MBS broadcast frequency used by NTN cells that are about to expire, or to restrict UE from reselecting to an NTN cell that is about to expire while providing MBS broadcast service.

A further potential issue may relate to determining the timing for MCCH monitoring in NTN. In Rel-17 MBS, UE monitors MCCH to receive the MBS configuration for broadcast session. And when an MCCH change notification is received, UE monitors MCCH to update the MBS configuration for broadcast session. MCCH uses a modification period and MCCH contents are only allowed to be modified at each modification period boundary. A notification mechanism is used to announce the change of MCCH contents due to broadcast session start, modification or stop and due to neighboring cell information modification. It is up to UE implementation how to address a possibility of the UE missing an MCCH change notification.

For the initial MCCH monitoring, in TN a UE starts to monitor upon entering the cell providing SIB20. In an NTN cell which could be much larger than an MBS broadcast service area, similar to that in the issue of providing MBS broadcast service in a geographical area smaller than an NTN cell, UE may not need to start MCCH monitoring upon entering the NTN cell, i.e., whether the UE is authorized to receive MBS broadcast service also affects UE in determining when to start monitoring the MCCH.

Meanwhile, in NTN UE needs to ensure a valid UE location information (e.g., via GNSS measurement) and a valid ephemeris data (in SIB19) for uplink synchronization. UE performing GNSS measurements or re-acquiring SIB19 in NTN may possibly miss the change notification. In such case, enhancements can be considered to accelerate UE in awareness of MCCH change and re-acquire MCCH configuration.

In view of the above discussions and analysis, some embodiments of the present disclosure provide solutions for providing a broadcast service in an NTN. In the solutions, a UE receives from a base station a first configuration for a broadcast service in a NTN, and performs broadcast service management based on the first configuration. In some implementations of the solution, the first configuration comprises configuration information for the user equipment to determine whether to receive the broadcast service from the base station. In some implementations of the solution, the first configuration comprises a stop serving time or a feeder link switch time of at least one neighbor cell in the NTN that supports the broadcast service. In some implementations of the solution, the first configuration comprises an indication of acquiring an MCCH configuration in the case that the user equipment does not receive an MCCH change notification at an MCCH modification period boundary.

In this way, some potential issues of supporting broadcast services (e.g., MBS broadcast services) in NTN scenarios can be solved. Some embodiments of the present disclosure relate to the NTN characteristics including a large cell size (e.g., larger than MBS broadcast service area) , cell change due to satellite movement and necessary information acquiring for uplink (UL) synchronization. The solutions can efficiently indicate whether UE in an NTN cell can receive broadcast services, so as to avoid unnecessary cell reselection (e.g., intra-/inter-frequency and inter-RAT cell reselection) and to enable/disable MCCH monitoring when necessary.

FIG. 1A illustrates an example of a wireless communications system 100 that supports performing PUSCH retransmissions in accordance with aspects of the present disclosure. The wireless communications system 100 may include one or more network entities 102 (also referred to as network equipment (NE) ) , one or more UEs 104, a core network 106, and a packet data network 108. The wireless communications system 100 may support various radio access technologies. In some implementations, the wireless communications system 100 may be a 4G network, such as an LTE network or an LTE-Advanced (LTE-A) network. In some other implementations, the wireless communications system 100 may be a 5G network, such as an NR network. In other implementations, the wireless communications system 100 may be a combination of a 4G network and a 5G network, or other suitable radio access technology including Institute of Electrical and Electronics Engineers (IEEE) 802.11 (Wi-Fi) , IEEE 802.16 (WiMAX) , IEEE 802.20. The wireless communications system 100 may support radio access technologies beyond 5G. Additionally, the wireless communications system 100 may support technologies, such as time division multiple access (TDMA) , frequency division multiple access (FDMA) , or code division multiple access (CDMA) , etc.

The one or more network entities 102 may be dispersed throughout a geographic region to form the wireless communications system 100. One or more of the network entities 102 described herein may be or include or may be referred to as a network node, a base station, a network element, a radio access network (RAN) , a base transceiver station, an access point, a NodeB, an eNodeB (eNB) , a next-generation NodeB (gNB) , or other suitable terminology. A network entity 102 and a UE 104 may communicate via a communication link 110, which may be a wireless or wired connection. For example, a network entity 102 and a UE 104 may perform wireless communication (e.g., receive signaling, transmit signaling) over a Uu interface.

In NTN scenarios, a network entity 102 in form of a satellite can directly communicate to UE 104 using NR/LTE Uu interface. The satellite may be a transparent satellite or a regenerative satellite. For NTN with a transparent satellite, a base station on earth may communicate with a UE via the satellite. For NTN with a regenerative satellite, the base station may be on board and directly communicate with the UE.

A network entity 102 may provide a geographic coverage area 112 for which the network entity 102 may support services (e.g., voice, video, packet data, messaging, broadcast, etc. ) for one or more UEs 104 within the geographic coverage area 112. For example, a network entity 102 and a UE 104 may support wireless communication of signals related to services (e.g., voice, video, packet data, messaging, broadcast, etc. ) according to one or multiple radio access technologies. In some implementations, a network entity 102 may be moveable, for example, a satellite associated with a non-terrestrial network. In some implementations, different geographic coverage areas 112 associated with the same or different radio access technologies may overlap, but the different geographic coverage areas 112 may be associated with different network entities 102. Information and signals described herein may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referenced throughout the description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

The one or more UEs 104 may be dispersed throughout a geographic region of the wireless communications system 100. A UE 104 may include or may be referred to as a mobile device, a wireless device, a remote device, a remote unit, a handheld device, or a subscriber device, or some other suitable terminology. In some implementations, the UE 104 may be referred to as a unit, a station, a terminal, or a client, among other examples. Additionally, or alternatively, the UE 104 may be referred to as an Internet-of-Things (IoT) device, an Internet-of-Everything (IoE) device, or machine-type communication (MTC) device, among other examples. In some implementations, a UE 104 may be stationary in the wireless communications system 100. In some other implementations, a UE 104 may be mobile in the wireless communications system 100.

The one or more UEs 104 may be devices in different forms or having different capabilities. Some examples of UEs 104 are illustrated in FIG. 1A. A UE 104 may be capable of communicating with various types of devices, such as the network entities 102, other UEs 104, or network equipment (e.g., the core network 106, the packet data network 108, a relay device, an integrated access and backhaul (IAB) node, or another network equipment) , as shown in FIG. 1A. Additionally, or alternatively, a UE 104 may support communication with other network entities 102 or UEs 104, which may act as relays in the wireless communications system 100.

A UE 104 may also be able to support wireless communication directly with other UEs 104 over a communication link 114. For example, a UE 104 may support wireless communication directly with another UE 104 over a device-to-device (D2D) communication link. In some implementations, such as vehicle-to-vehicle (V2V) deployments, vehicle-to-everything (V2X) deployments, or cellular-V2X deployments, the communication link 114 may be referred to as a sidelink. For example, a UE 104 may support wireless communication directly with another UE 104 over a PC5 interface.

A network entity 102 may support communications with the core network 106, or with another network entity 102, or both. For example, a network entity 102 may interface with the core network 106 through one or more backhaul links 116 (e.g., via an S1, N2, N2, or another network interface) . The network entities 102 may communicate with each other over the backhaul links 116 (e.g., via an X2, Xn, or another network interface) . In some implementations, the network entities 102 may communicate with each other directly (e.g., between the network entities 102) . In some other implementations, the network entities 102 may communicate with each other or indirectly (e.g., via the core network 106) . In some implementations, one or more network entities 102 may include subcomponents, such as an access network entity, which may be an example of an access node controller (ANC) . An ANC may communicate with the one or more UEs 104 through one or more other access network transmission entities, which may be referred to as a radio heads, smart radio heads, or transmission-reception points (TRPs) .

In some implementations, a network entity 102 may be configured in a disaggregated architecture, which may be configured to utilize a protocol stack physically or logically distributed among two or more network entities 102, such as an integrated access backhaul (IAB) network, an open RAN (O-RAN) (e.g., a network configuration sponsored by the O-RAN Alliance) , or a virtualized RAN (vRAN) (e.g., a cloud RAN (C-RAN) ) . For example, a network entity 102 may include one or more of a central unit (CU) , a distributed unit (DU) , a radio unit (RU) , a RAN Intelligent Controller (RIC) (e.g., a Near-Real Time RIC (Near-RT RIC) , a Non-Real Time RIC (Non-RT RIC) ) , a Service Management and Orchestration (SMO) system, or any combination thereof.

An RU may also be referred to as a radio head, a smart radio head, a remote radio head (RRH) , a remote radio unit (RRU) , or a transmission reception point (TRP) . One or more components of the network entities 102 in a disaggregated RAN architecture may be co-located, or one or more components of the network entities 102 may be located in distributed locations (e.g., separate physical locations) . In some implementations, one or more network entities 102 of a disaggregated RAN architecture may be implemented as virtual units (e.g., a virtual CU (VCU) , a virtual DU (VDU) , a virtual RU (VRU) ) .

Split of functionality between a CU, a DU, and an RU may be flexible and may support different functionalities depending upon which functions (e.g., network layer functions, protocol layer functions, baseband functions, radio frequency functions, and any combinations thereof) are performed at a CU, a DU, or an RU. For example, a functional split of a protocol stack may be employed between a CU and a DU such that the CU may support one or more layers of the protocol stack and the DU may support one or more different layers of the protocol stack. In some implementations, the CU may host upper protocol layer (e.g., a layer 3 (L3) , a layer 2 (L2) ) functionality and signaling (e.g., Radio Resource Control (RRC) , service data adaption protocol (SDAP) , Packet Data Convergence Protocol (PDCP) ) . The CU may be connected to one or more DUs or RUs, and the one or more DUs or RUs may host lower protocol layers, such as a layer 1 (L1) (e.g., physical (PHY) layer) or an L2 (e.g., radio link control (RLC) layer, medium access control (MAC) layer) functionality and signaling, and may each be at least partially controlled by the CU 160.

Additionally, or alternatively, a functional split of the protocol stack may be employed between a DU and an RU such that the DU may support one or more layers of the protocol stack and the RU may support one or more different layers of the protocol stack. The DU may support one or multiple different cells (e.g., via one or more RUs) . In some implementations, a functional split between a CU and a DU, or between a DU and an RU may be within a protocol layer (e.g., some functions for a protocol layer may be performed by one of a CU, a DU, or an RU, while other functions of the protocol layer are performed by a different one of the CU, the DU, or the RU) .

A CU may be functionally split further into CU control plane (CU-CP) and CU user plane (CU-UP) functions. A CU may be connected to one or more DUs via a midhaul communication link (e.g., F1, F1-c, F1-u) , and a DU may be connected to one or more RUs via a fronthaul communication link (e.g., open fronthaul (FH) interface) . In some implementations, a midhaul communication link or a fronthaul communication link may be implemented in accordance with an interface (e.g., a channel) between layers of a protocol stack supported by respective network entities 102 that are in communication via such communication links.

The core network 106 may support user authentication, access authorization, tracking, connectivity, and other access, routing, or mobility functions. The core network 106 may be an evolved packet core (EPC) , or a 5G core (5GC) , which may include a control plane entity that manages access and mobility (e.g., a mobility management entity (MME) , an access and mobility management functions (AMF) ) and a user plane entity that routes packets or interconnects to external networks (e.g., a serving gateway (S-GW) , a Packet Data Network (PDN) gateway (P-GW) , or a user plane function (UPF) ) . In some implementations, the control plane entity may manage non-access stratum (NAS) functions, such as mobility, authentication, and bearer management (e.g., data bearers, signal bearers, etc. ) for the one or more UEs 104 served by the one or more network entities 102 associated with the core network 106.

The core network 106 may communicate with the packet data network 108 over one or more backhaul links 116 (e.g., via an S1, N2, N2, or another network interface) . The packet data network 108 may include an application server 118. In some implementations, one or more UEs 104 may communicate with the application server 118. A UE 104 may establish a session (e.g., a protocol data unit (PDU) session, or the like) with the core network 106 via a network entity 102. The core network 106 may route traffic (e.g., control information, data, and the like) between the UE 104 and the application server 118 using the established session (e.g., the established PDU session) . The PDU session may be an example of a logical connection between the UE 104 and the core network 106 (e.g., one or more network functions of the core network 106) .

In the wireless communications system 100, the network entities 102 and the UEs 104 may use resources of the wireless communications system 100 (e.g., time resources (e.g., symbols, slots, subframes, frames, or the like) or frequency resources (e.g., subcarriers, carriers) ) to perform various operations (e.g., wireless communications) . In some implementations, the network entities 102 and the UEs 104 may support different resource structures. For example, the network entities 102 and the UEs 104 may support different frame structures. In some implementations, such as in 4G, the network entities 102 and the UEs 104 may support a single frame structure. In some other implementations, such as in 5G and among other suitable radio access technologies, the network entities 102 and the UEs 104 may support various frame structures (i.e., multiple frame structures) . The network entities 102 and the UEs 104 may support various frame structures based on one or more numerologies.

One or more numerologies may be supported in the wireless communications system 100, and a numerology may include a subcarrier spacing and a cyclic prefix. A first numerology (e.g., μ=0) may be associated with a first subcarrier spacing (e.g., 15 kHz) and a normal cyclic prefix. In some implementations, the first numerology (e.g., μ=0) associated with the first subcarrier spacing (e.g., 15 kHz) may utilize one slot per subframe. A second numerology (e.g., μ=1) may be associated with a second subcarrier spacing (e.g., 30 kHz) and a normal cyclic prefix. A third numerology (e.g., μ=2) may be associated with a third subcarrier spacing (e.g., 60 kHz) and a normal cyclic prefix or an extended cyclic prefix. A fourth numerology (e.g., μ=3) may be associated with a fourth subcarrier spacing (e.g., 120 kHz) and a normal cyclic prefix. A fifth numerology (e.g., μ=4) may be associated with a fifth subcarrier spacing (e.g., 240 kHz) and a normal cyclic prefix.

A time interval of a resource (e.g., a communication resource) may be organized according to frames (also referred to as radio frames) . Each frame may have a duration, for example, a 10 millisecond (ms) duration. In some implementations, each frame may include multiple subframes. For example, each frame may include 10 subframes, and each subframe may have a duration, for example, a 1 ms duration. In some implementations, each frame may have the same duration. In some implementations, each subframe of a frame may have the same duration.

Additionally, or alternatively, a time interval of a resource (e.g., a communication resource) may be organized according to slots. For example, a subframe may include a number (e.g., quantity) of slots. The number of slots in each subframe may also depend on the one or more numerologies supported in the wireless communications system 100. For instance, the first, second, third, fourth, and fifth numerologies (i.e., μ=0, μ=1, μ=2, μ=3, μ=4) associated with respective subcarrier spacings of 15 kHz, 30 kHz, 60 kHz, 120 kHz, and 240 kHz may utilize a single slot per subframe, two slots per subframe, four slots per subframe, eight slots per subframe, and 16 slots per subframe, respectively. Each slot may include a number (e.g., quantity) of symbols (e.g., OFDM symbols) . In some implementations, the number (e.g., quantity) of slots for a subframe may depend on a numerology. For a normal cyclic prefix, a slot may include 14 symbols. For an extended cyclic prefix (e.g., applicable for 60 kHz subcarrier spacing) , a slot may include 12 symbols. The relationship between the number of symbols per slot, the number of slots per subframe, and the number of slots per frame for a normal cyclic prefix and an extended cyclic prefix may depend on a numerology. It should be understood that reference to a first numerology (e.g., μ=0) associated with a first subcarrier spacing (e.g., 15 kHz) may be used interchangeably between subframes and slots.

In the wireless communications system 100, an electromagnetic (EM) spectrum may be split, based on frequency or wavelength, into various classes, frequency bands, frequency channels, etc. By way of example, the wireless communications system 100 may support one or multiple operating frequency bands, such as frequency range designations FR1 (410 MHz –7.125 GHz) , FR2 (24.25 GHz –52.6 GHz) , FR3 (7.125 GHz –24.25 GHz) , FR4 (52.6 GHz –114.25 GHz) , FR4a or FR4-1 (52.6 GHz –71 GHz) , and FR5 (114.25 GHz –300 GHz) . In some implementations, the network entities 102 and the UEs 104 may perform wireless communications over one or more of the operating frequency bands. In some implementations, FR1 may be used by the network entities 102 and the UEs 104, among other equipment or devices for cellular communications traffic (e.g., control information, data) . In some implementations, FR2 may be used by the network entities 102 and the UEs 104, among other equipment or devices for short-range, high data rate capabilities.

FR1 may be associated with one or multiple numerologies (e.g., at least three numerologies) . For example, FR1 may be associated with a first numerology (e.g., μ=0) , which includes 15 kHz subcarrier spacing; a second numerology (e.g., μ=1) , which includes 30 kHz subcarrier spacing; and a third numerology (e.g., μ=2) , which includes 60 kHz subcarrier spacing. FR2 may be associated with one or multiple numerologies (e.g., at least 2 numerologies) . For example, FR2 may be associated with a third numerology (e.g., μ=2) , which includes 60 kHz subcarrier spacing; and a fourth numerology (e.g., μ=3) , which includes 120 kHz subcarrier spacing.

For the purpose of illustration without suggesting any limitations, some embodiments of the present disclosure will be described with reference to the scenario that a UE 104 performs PUSCH transmissions and retransmissions to a network entity 102. It is to be understood that the disclosure described herein may be implemented in various manners other than the ones described below.

FIG. 1B illustrates an example diagram of relation between an MBS broadcast service area and cell coverage in the TN and NTN. In FIG. 1B, TN cells #1, #2 and #3 are in the MBS broadcast service area 151, and TN cells #4 and #5 are not in the MBS broadcast service area 151. As indicated above, in Rel-17 MBS designed for TN, UE can simply judge whether it is in an MBS broadcast service area by its serving cell and the corresponding MBS broadcast configuration it receives. However, as shown in FIG. 1B, the NTN cell #1 provided by the network entity 102 may cover a larger area 153 beyond the MBS broadcast service area 152. As a result, the MBS designed for TN is not workable for NTN scenarios.

FIG. 2 illustrates an example signaling chart of an example process 200 that supports a broadcast service in an NTN in accordance with aspects of the present disclosure. For the purpose of discussion, the process 200 will be described with reference to FIG. 1A, and the process 200 may involve a UE 104 and a network entity 102 as shown in FIG. 1A. The network entity 102 may be also referred to as the base station 102. In some embodiments, the base station 102 may be located at a satellite or communicates with the UE 104 via a satellite.

As shown in FIG. 2, the base station 102 determines 201 a first configuration for a broadcast service in an NTN, and transmits 202 the first configuration 203 to the UE 104. The UE 104 receives 204 the first configuration, and performs 205 broadcast service management based on the first configuration. In this way, the UE 104 in an NTN cell can efficiently determine whether to receive a broadcast service, so as to avoid unnecessary cell reselection and to enable/disable MCCH monitoring when necessary.

Some embodiments of the present disclosure will be described in details below in combination with the potential issues to be solved. It would be appreciated that the embodiments of the present disclosure may be applied to other scenarios or cases.

With respect to the potential issue relating to providing MBS broadcast service in a geographical area smaller than an NTN cell, some embodiments of the present disclosure provide enhancements for MBS broadcast service area indication in an NTN cell with coverage larger than it. For example, the base station 102 may indicate additional information of MBS broadcast service area to UE 104, and UE 104 may determine to receive/process an MBS broadcast service based on the information.

Specifically, in some embodiments, the first configuration may comprise configuration information for the UE 104 to determine whether to receive the broadcast service from the base station 102. The configuration information may comprise a parameter associated with an area of the broadcast service.

The parameter may be an explicit parameter of MBS broadcast service area. For example, the parameter may comprise a reference location and a radius forming a circle. In this case, the parameter indicates a circle for the MBS broadcast service area. Additionally, or alternatively, the parameter may comprise more than one location forming a line (s) or a shape. In this case, the parameter indicates a regular or irregular shape for the MBS broadcast service area.

In some embodiments, the UE 104 may determine whether to receive the broadcast service by determining whether a criterion indicated by the parameter is fulfilled. In the case that the parameter explicitly indicates the MBS broadcast service area, the criterion may comprise the UE 104 is in the area indicated by the parameter.

In this case, when the UE 104 is in the indicated area, the UE 104 may apply corresponding MBS configuration for broadcast and receive the broadcast service from the base station 102. Alternatively, when the UE 104 is out of the indicated area, the UE 104 may not apply corresponding MBS configuration for broadcast and not receive the broadcast service from the base station 102.

MBS configuration for broadcast (e.g., MBSBroadcastConfiguration) or part of MBS configuration for broadcast (e.g., MBS-SessionInfoList) may be associated with the area parameter. In other words, the information of MBS broadcast service area including the area parameter can be associated with or included in at least one of: Cell-specific MBS configuration for broadcast (e.g., IE MBSBroadcastConfiguration) ; or Service/Session-specific MBS configuration for broadcast (e.g., IE MBS-SessionInfoList) .

In some embodiments, the MBS broadcast service area may be associated with/mapped to an alternative parameter. For example, the parameter associated with an area of the broadcast service may comprise one of the following: an identity of a beam in a serving cell of the NTN, an identity of an RAN notification area, an angle threshold for an angle between the UE 104 and a satellite that provides the serving cell, a first time threshold for a propagation delay between the UE 104 and the satellite or the base station 102, or a second time threshold for a timing advance between the UE 104 and the satellite or the base station 102.

Corresponding to the respective alternative parameter, the criterion for the UE 104 determining whether to receive the broadcast service may comprise one of the following: the UE 104 selects the beam indicated by the identity of the beam, the UE 104 is in the RAN notification area, the angle between the UE 104 and the satellite is smaller or larger than the angle threshold, the propagation delay is smaller or larger than the first time threshold, or the timing advance is smaller or larger than the second time threshold.

When the criterion is fulfilled, the UE 104 may apply corresponding MBS configuration for broadcast and receive the broadcast service from the base station 102. Alternatively, when the criterion is not fulfilled, the UE 104 may not apply corresponding MBS configuration for broadcast and not receive the broadcast service from the base station 102.

In this case, MBS configuration for broadcast (e.g., MBSBroadcastConfiguration) or part of MBS configuration for broadcast (e.g., MBS-SessionInfoList) may be associated with the alternative parameter. In other words, the information of MBS broadcast service area including the alternative parameter can be associated with or included in at least one of: Cell-specific MBS configuration for broadcast (e.g., IE MBSBroadcastConfiguration) ; or Service/Session-specific MBS configuration for broadcast (e.g., IE MBS-SessionInfoList) .

In some embodiments, UE 104 may be provide an explicit indication of enabling/disabling reception of a broadcast service. For example, the base station 102 may generate an indication indicating whether UE 104 can receive an MBS broadcast service based on knowledge of UE location or verification. Optionally, the indication can further include a validity duration.

With an indication of enabling, or no indication of disabling, UE 104 can receive the corresponding MBS broadcast service. With no indication of enabling or an indication of enabling expiry or an indication of disabling, UE 104 cannot receive the corresponding MBS broadcast service.

In this case, MBS configuration for broadcast (e.g., MBSBroadcastConfiguration) or part of MBS configuration for broadcast (e.g., MBS-SessionInfoList) may be associated with the indication. In other words, the information of MBS broadcast service area including the indication can be associated with or included in at least one of: Cell-specific MBS configuration for broadcast (e.g., IE MBSBroadcastConfiguration) ; or Service/Session-specific MBS configuration for broadcast (e.g., IE MBS-SessionInfoList) .

With respect to the potential issue relating to handling the frequency priority and cell reselection rules dedicated for an MBS broadcast service in NTN, some embodiments of the present disclosure provide IDLE/INACTIVE mobility handling for MBS broadcast services with consideration of NTN cell validity.

In some embodiments, the first configuration may comprise a stop serving time (e.g., t-Service) or a feeder link switch time (e.g., t-FeederLinkSwitch) of at least one neighbor cell in the NTN that supports the broadcast service.

In one case, for MBS broadcast services provided via NTN, UE may be restricted to consider an NTN cell frequency to be the highest priority during the MBS broadcast session, e.g., when the corresponding NTN cell is approaching t-Service (or t-FeederLinkSwitch) or if the corresponding NTN cell is generated by an NGSO satellite.

For example, the UE 104 may determine a frequency priority for the broadcast service based on the stop serving time or the feeder link switch time of the at least one neighbor cell. When determining the frequency priority for the broadcast service, the UE 104 may by restricted to consider a frequency to be the highest priority during a broadcast session of the broadcast service, in the case that a condition is fulfilled. The condition comprises one of the following: the at least one neighbor cell using the frequency is approaching the stop serving time or the feeder link switch time, remaining time before the stop serving time or the feeder link switch time is less than a threshold, or remaining time before the stop serving time or the feeder link switch time is less than an expected reception duration of the broadcast service at the user equipment. The TN cell can be considered as with infinite t-Service or t-FeederLinkSwitch.

In another case, for MBS broadcast services provided via NTN, UE may be allowed to consider an NTN cell frequency to be the highest priority during the MBS broadcast session, and cell reselection to an NTN cell approaching t-Service (or t-FeederLinkSwitch) is optimized regarding its remaining time.

Specifically, the UE 104 may apply an offset to a parameter value for a cell reselection based on the stop serving time or the feeder link switch time. The cell reselection may comprise one of the following: a non-equal inter-frequency cell reselection, an inter-RAT cell reselection, an intra-frequency cell reselection, or an equal priority inter-frequency cell reselection.

For instance, the UE 104 may apply an RSRP offset to an RSRP threshold for the cell reselection. As an example, for the non-equal inter-frequency and inter-RAT cell reselection, the cell reselection to a cell on a higher priority NR frequency or inter-RAT frequency than the serving frequency can be performed if a cell of a higher priority NR or EUTRAN RAT/frequency fulfils Srxlev > Thresh_X, HighP + Offset_X, HighP during a time interval Treselection_RAT. For the intra-frequency cell reselection and equal priority inter-frequency cell reselection, the cell-ranking criterion R_n for neighbouring cells may be defined by R_n = Q_meas, n -Qoffset -Qoffset_MBS.

Additionally, or alternatively, the UE 104 may apply an RSRQ offset to an RSRQ threshold for the cell reselection. As an example, the cell reselection to a cell on a higher priority NR frequency or inter-RAT frequency than the serving frequency can be performed if a cell of a higher priority NR or EUTRAN RAT/frequency fulfils Squal > Thresh_X, HighQ +Offset_X, HighQ during a time interval Treselection_RAT. For the intra-frequency cell reselection and equal priority inter-frequency cell reselection, the cell-ranking criterion R_n for neighbouring cells may be defined by R_n = Q_meas, n -Qoffset -Qoffset_MBS.

Additionally, or alternatively, the UE 104 may apply a time offset to a time threshold for the cell reselection. As an example, the cell reselection to a cell on a higher priority NR frequency or inter-RAT frequency than the serving frequency can be performed if a cell of a higher priority NR or EUTRAN RAT/frequency fulfils Srxlev > Thresh_X, HighP (or Squal > Thresh_X, HighQ) during a time interval Treselection_RAT + Offset_{Treselection, RAT}.

The offset may be associated with remaining time before the stop serving time or the feeder link switch time. For example, the offset can be further associated to the remaining time before t-Service (or t-FeederLinkSwitch) of one or all neighbour cells using the frequency and/or the expected reception duration of the corresponding MBS broadcast service at UE.

In some implementations, the stop serving time or the feeder link switch time may be provided to the UE 104 in SIB2 associated with the at least one neighbor cell, an SIB19 associated with the at least one neighbor cell, an SIB20 associated with an MBS configuration for broadcast (e.g., MBSBroadcastConfiguration) or part of the MBS configuration for broadcast (e.g., MBS-NeighbourCellList) , an SIB21 associated with a frequency or a FSAI, or dedicated signalling e.g., RRCRelease.

With respect to the potential issue relating to determining the timing for MCCH monitoring in NTN, some embodiments of the present disclosure provide new criterion for the UE monitoring the MCCH.

For a MBS broadcast service, UE 104 may determine when to start monitoring the MCCH using the start and stop times in the USD and whether a criterion is fulfilled. For example, the base station 102 may generate and indicate one of the following to UE 104: information of MBS broadcast service area including the explicit area parameter, information of MBS broadcast service area including the alternative parameter, or an indication indicating whether UE 104 can receive an MBS broadcast service. Correspondingly, UE 104 may determine when to start or stop monitoring the MCCH based on one of: whether UE 104 is in or out of the area indicated by the area parameter, whether UE 104 fulfils or does not fulfil the criterion defined by the alternative parameter, or whether UE 104 receives the indication of enabling or disabling reception of an MBS broadcast service.

In other words, the criterion for start or stop monitoring the MCCH may be the same as that for determining whether to receive the broadcast service. If the UE 104 determines to receive the broadcast service from the base station 102, it may monitor the MCCH corresponding to the broadcast service. If the UE 104 determines not to receive the broadcast service from the base station 102, it may not monitor the MCCH corresponding to the broadcast service.

In some embodiments, when the UE 104 possibly misses a MCCH content change notification in NTN, it may update the MCCH configuration. For example, the first configuration may comprise an indication of acquiring an MCCH configuration in the case that the UE 104 does not receive an MCCH change notification at an MCCH modification period boundary.

The UE 104 may automatically update the MCCH configuration. For example, the UE 104 may acquire an MCCH configuration in SIB20 after a GNSS measurement is complete or after acquiring SIB19 is complete. Alternatively, the UE 104 may conditionally update the MCCH configuration. For example, the UE 104 may acquire an MCCH configurationin in SIB20 after a GNSS measurement is complete if the corresponding process duration covers an MCCH modification period boundary, after a GNSS measurement is complete if an MCCH change notification is received in network response for GNSS result reporting, after acquiring SIB19 is complete if the corresponding process duration covers an MCCH modification period boundary, or after acquiring SIB19 is complete if an MCCH change notification is received in the acquired SIB19. The MCCH change notification in SIB19 may not trigger SIB19 update. Alternatively, the UE 104 may acquire an MCCH configurationin in a network response for GNSS result reporting or in SIB19.

FIG. 3 illustrates an example procedure 300 that supports a broadcast service in an NTN in accordance with aspects of the present disclosure. The procedure 300 can be an example of the process 200 as shown in FIG. 2. The procedure 300 may involve the UE 104 and the base station 102 as shown in FIG. 2 and a core network device 301.

As shown in FIG. 3, at 302, the core network device 301 may transmit a USD for MBS for broadcast services to the UE 104. The base station 102 may transmit to the UE 104a MBS configuration for broadcast at 303, and transmit to the UE 104 information of MBS broadcast services of a neighbor cell (s) .

At 305, the base station 102 may transmit to the UE 104 a first configuration for a broadcast service in an NTN. For example, the first configuration may comprise information of MBS broadcast service area within an NTN cell, such as the explicit area parameter, the alternative parameter associated with/mapped to the MBS broadcast service area, or an indication indicating whether UE can receive an MBS broadcast service, and optionally a validity duration for the indication.

In some embodiments, the first configuration may further comprise the stop serving time or feeder link switch time of at least one neighbor cell that supports broadcast services. In some embodiments, the first configuration may further comprise an indication of acquiring the MCCH configuration if the UE 104 does not receive a MCCH change notification at an MCCH modification period boundary.

The UE 104 may determine whether to monitor the MCCH based on the information or indication comprised in the first configuration at 306. At 307, the UE 104 may determine whether to receive an MBS configuration for broadcast based on the information or indication comprised in the first configuration.

For example, when the UE 104 is in or out of the area indicated by the area parameters, the UE 104 may apply or not apply the corresponding MBS configuration for broadcast, or the UE 104 may receive or not receive the corresponding MBS broadcast service in the serving cell, or the UE 104 may monitor or not monitor the corresponding MCCH.

Additionally, or alternatively, when the UE 104 fulfils or does not fulfil the criterion defined by the alternative parameter, the UE 104 may apply or not apply the corresponding MBS configuration for broadcast, or the UE 104 may receive or not receive the corresponding MBS broadcast service in the serving cell, or the UE 104 may monitor or not monitor the corresponding MCCH.

The criterion defined by the alternative parameter could be at least one of: the UE 104 selects the beam indicated by the received identity of a beam in serving cell; the UE 104 is in the RAN Notification Area (s) indicated by the received identity of RAN Notification Area (s) ; an elevation angle between the UE 104 and a satellite is smaller or larger than an indicated angle threshold; or a propagation delay or timing advance between the UE 104 and a satellite or gNB is smaller or larger than an indicated time threshold.

When UE receives the indication of enabling or disabling a reception of the MBS broadcast service, the UE 104 may apply or not apply the corresponding MBS configuration for broadcast, or the UE 104 may receive or not receive the corresponding MBS broadcast service in the serving cell, or the UE 104 may monitor or not monitor the corresponding MCCH.

At 308, the UE 104 may determine a frequency priority for broadcast services based on the stop serving time (e.g., t-Service) or feeder link switch time (e.g., t-FeederLinkSwitch) of at least one neighbor cell that supports broadcast services.

At 309, the UE 104 may perform a cell reselection based on the stop serving time or the feeder link switch time. For example, the UE 104 may apply an offset to a parameter value for the cell reselection, such as the intra-frequency, inter-frequency with equal or non-equal priority, or inter-RAT cell reselection.

At 310, the UE 104 may acquire an MCCH configuration in at least one of the following conditions: after a GNSS measurement is complete; after a GNSS measurement is complete if the corresponding measurement duration covers an MCCH modification period boundary; after a GNSS measurements is complete if an MCCH change notification is received in network response for GNSS result reporting; after acquiring SIB19 is complete; after acquiring SIB19 is complete if the corresponding acquiring duration covers an MCCH modification period boundary; after acquiring SIB19 is complete if an MCCH change notification is received in the acquired SIB19.

It should be understood that the base station 102 may perform operations corresponding to the UE 104 even though these operations are not explicitly described for the sake of brevity.

FIG. 4 illustrates an example of a device 400 that supports a broadcast service in an NTN in accordance with aspects of the present disclosure. The device 400 may be an example of the UE 104 or the base station 102 as described herein. The device 400 may support wireless communication with one or more base stations 102, UEs 104, or any combination thereof. The device 400 may include components for bi-directional communications including components for transmitting and receiving communications, such as a processor 402, a memory 404, a transceiver 406, and, optionally, an I/O controller 408. These components may be in electronic communication or otherwise coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more interfaces (e.g., buses) .

The processor 402, the memory 404, the transceiver 406, or various combinations thereof or various components thereof may be examples of means for performing various aspects of the present disclosure as described herein. For example, the processor 402, the memory 404, the transceiver 406, or various combinations or components thereof may support a method for performing one or more of the operations described herein.

In some implementations, the processor 402, the memory 404, the transceiver 406, or various combinations or components thereof may be implemented in hardware (e.g., in communications management circuitry) . The hardware may include a processor, a digital signal processor (DSP) , an application-specific integrated circuit (ASIC) , a field-programmable gate array (FPGA) or other programmable logic device, a discrete gate or transistor logic, discrete hardware components, or any combination thereof configured as or otherwise supporting a means for performing the functions described in the present disclosure. In some implementations, the processor 402 and the memory 404 coupled with the processor 402 may be configured to perform one or more of the functions described herein (e.g., executing, by the processor 402, instructions stored in the memory 404) .

For example, the processor 402 may support wireless communication at the device 400 in accordance with examples as disclosed herein. The processor 402 may be configured to operable to support a means for transmitting a plurality of PUSCH transmissions through a plurality of TOs in a period of a CG configuration; a means for determining a plurality of resources for retransmissions of at least some of the PUSCH transmissions; and a means for retransmitting the at least some of the PUSCH transmissions using the plurality of determined resources.

The processor 402 may include an intelligent hardware device (e.g., a general-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, an FPGA, a programmable logic device, a discrete gate or transistor logic component, a discrete hardware component, or any combination thereof) . In some implementations, the processor 402 may be configured to operate a memory array using a memory controller. In some other implementations, a memory controller may be integrated into the processor 402. The processor 402 may be configured to execute computer-readable instructions stored in a memory (e.g., the memory 404) to cause the device 400 to perform various functions of the present disclosure.

The memory 404 may include random access memory (RAM) and read-only memory (ROM) . The memory 404 may store computer-readable, computer-executable code including instructions that, when executed by the processor 402 cause the device 400 to perform various functions described herein. The code may be stored in a non-transitory computer-readable medium such as system memory or another type of memory. In some implementations, the code may not be directly executable by the processor 402 but may cause a computer (e.g., when compiled and executed) to perform functions described herein. In some implementations, the memory 404 may include, among other things, a basic I/O system (BIOS) which may control basic hardware or software operation such as the interaction with peripheral components or devices.

The I/O controller 408 may manage input and output signals for the device 400. The I/O controller 408 may also manage peripherals not integrated into the device M02. In some implementations, the I/O controller 408 may represent a physical connection or port to an external peripheral. In some implementations, the I/O controller 408 may utilize an operating system such as or another known operating system. In some implementations, the I/O controller 408 may be implemented as part of a processor, such as the processor 406. In some implementations, a user may interact with the device 400 via the I/O controller 408 or via hardware components controlled by the I/O controller 408.

In some implementations, the device 400 may include a single antenna 410. However, in some other implementations, the device 400 may have more than one antenna 410 (i.e., multiple antennas) , including multiple antenna panels or antenna arrays, which may be capable of concurrently transmitting or receiving multiple wireless transmissions. The transceiver 406 may communicate bi-directionally, via the one or more antennas 410, wired, or wireless links as described herein. For example, the transceiver 406 may represent a wireless transceiver and may communicate bi-directionally with another wireless transceiver. The transceiver 406 may also include a modem to modulate the packets, to provide the modulated packets to one or more antennas 410 for transmission, and to demodulate packets received from the one or more antennas 410. The transceiver 406 may include one or more transmit chains, one or more receive chains, or a combination thereof.

A transmit chain may be configured to generate and transmit signals (e.g., control information, data, packets) . The transmit chain may include at least one modulator for modulating data onto a carrier signal, preparing the signal for transmission over a wireless medium. The at least one modulator may be configured to support one or more techniques such as amplitude modulation (AM) , frequency modulation (FM) , or digital modulation schemes like phase-shift keying (PSK) or quadrature amplitude modulation (QAM) . The transmit chain may also include at least one power amplifier configured to amplify the modulated signal to an appropriate power level suitable for transmission over the wireless medium. The transmit chain may also include one or more antennas 410 for transmitting the amplified signal into the air or wireless medium.

A receive chain may be configured to receive signals (e.g., control information, data, packets) over a wireless medium. For example, the receive chain may include one or more antennas 410 for receive the signal over the air or wireless medium. The receive chain may include at least one amplifier (e.g., a low-noise amplifier (LNA) ) configured to amplify the received signal. The receive chain may include at least one demodulator configured to demodulate the receive signal and obtain the transmitted data by reversing the modulation technique applied during transmission of the signal. The receive chain may include at least one decoder for decoding the processing the demodulated signal to receive the transmitted data.

FIG. 5 illustrates an example of a processor 500 that supports a broadcast service in an NTN in accordance with aspects of the present disclosure. The processor 500 may be an example of a processor configured to perform various operations in accordance with examples as described herein. The processor 500 may include a controller 502 configured to perform various operations in accordance with examples as described herein. The processor 500 may optionally include at least one memory 504, such as L1/L2/L3 cache. Additionally, or alternatively, the processor 500 may optionally include one or more arithmetic-logic units (ALUs) 500. One or more of these components may be in electronic communication or otherwise coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more interfaces (e.g., buses) .

The processor 500 may be a processor chipset and include a protocol stack (e.g., a software stack) executed by the processor chipset to perform various operations (e.g., receiving, obtaining, retrieving, transmitting, outputting, forwarding, storing, determining, identifying, accessing, writing, reading) in accordance with examples as described herein. The processor chipset may include one or more cores, one or more caches (e.g., memory local to or included in the processor chipset (e.g., the processor 500) or other memory (e.g., random access memory (RAM) , read-only memory (ROM) , dynamic RAM (DRAM) , synchronous dynamic RAM (SDRAM) , static RAM (SRAM) , ferroelectric RAM (FeRAM) , magnetic RAM (MRAM) , resistive RAM (RRAM) , flash memory, phase change memory (PCM) , and others) .

The controller 502 may be configured to manage and coordinate various operations (e.g., signaling, receiving, obtaining, retrieving, transmitting, outputting, forwarding, storing, determining, identifying, accessing, writing, reading) of the processor 500 to cause the processor 500 to support various operations in accordance with examples as described herein. For example, the controller 502 may operate as a control unit of the processor 500, generating control signals that manage the operation of various components of the processor 500. These control signals include enabling or disabling functional units, selecting data paths, initiating memory access, and coordinating timing of operations.

The controller 502 may be configured to fetch (e.g., obtain, retrieve, receive) instructions from the memory 504 and determine subsequent instruction (s) to be executed to cause the processor 500 to support various operations in accordance with examples as described herein. The controller 502 may be configured to track memory address of instructions associated with the memory 504. The controller 502 may be configured to decode instructions to determine the operation to be performed and the operands involved. For example, the controller 502 may be configured to interpret the instruction and determine control signals to be output to other components of the processor 500 to cause the processor 500 to support various operations in accordance with examples as described herein. Additionally, or alternatively, the controller 502 may be configured to manage flow of data within the processor 500. The controller 502 may be configured to control transfer of data between registers, arithmetic logic units (ALUs) , and other functional units of the processor 500.

The memory 504 may include one or more caches (e.g., memory local to or included in the processor 500 or other memory, such RAM, ROM, DRAM, SDRAM, SRAM, MRAM, flash memory, etc. In some implementation, the memory 504 may reside within or on a processor chipset (e.g., local to the processor 500) . In some other implementations, the memory 504 may reside external to the processor chipset (e.g., remote to the processor 500) .

The memory 504 may store computer-readable, computer-executable code including instructions that, when executed by the processor 500, cause the processor 500 to perform various functions described herein. The code may be stored in a non-transitory computer-readable medium such as system memory or another type of memory. The controller 502 and/or the processor 500 may be configured to execute computer-readable instructions stored in the memory 504 to cause the processor 500 to perform various functions. For example, the processor 500 and/or the controller 502 may be coupled with or to the memory 504, and the processor 500, the controller 502, and the memory 504 may be configured to perform various functions described herein. In some examples, the processor 500 may include multiple processors and the memory 504 may include multiple memories. One or more of the multiple processors may be coupled with one or more of the multiple memories, which may, individually or collectively, be configured to perform various functions herein.

The one or more ALUs 500 may be configured to support various operations in accordance with examples as described herein. In some implementation, the one or more ALUs 500 may reside within or on a processor chipset (e.g., the processor 500) . In some other implementations, the one or more ALUs 500 may reside external to the processor chipset (e.g., the processor 500) . One or more ALUs 500 may perform one or more computations such as addition, subtraction, multiplication, and division on data. For example, one or more ALUs 500 may receive input operands and an operation code, which determines an operation to be executed. One or more ALUs 500 be configured with a variety of logical and arithmetic circuits, including adders, subtractors, shifters, and logic gates, to process and manipulate the data according to the operation. Additionally, or alternatively, the one or more ALUs 500 may support logical operations such as AND, OR, exclusive-OR (XOR) , not-OR (NOR) , and not-AND (NAND) , enabling the one or more ALUs 500 to handle conditional operations, comparisons, and bitwise operations.

The processor 500 may support wireless communication in accordance with examples as disclosed herein. The processor 500 may be configured to or operable to support a means for receiving a first configuration for a broadcast service in an NTN; and a means for performing broadcast service management based on the first configuration.

In some embodiments, the processor 500 may be configured to or operable to support a means for determining a first configuration for a broadcast service in an NTN; and a means for transmitting the first configuration.

FIG. 6 illustrates a flowchart of a method 600 that supports a broadcast service in an NTN in accordance with aspects of the present disclosure. The operations of the method 600 may be implemented by a device or its components as described herein. For example, the operations of the method 600 may be performed by the UE 104 as described herein. In some implementations, the device may execute a set of instructions to control the function elements of the device to perform the described functions. Additionally, or alternatively, the device may perform aspects of the described functions using special-purpose hardware.

At block 605, the method may include receiving from a base station a first configuration for a broadcast service in an NTN. The operations of receiving the first configuration may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of receiving the first configuration may be performed by a device as described with reference to FIG. 1A.

At block 610, the method may include performing broadcast service management based on the first configuration. The operations of performing broadcast service management may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of performing broadcast service management may be performed by a device as described with reference to FIG. 1A.

In some embodiments, the first configuration may comprise configuration information for the user equipment to determine whether to receive the broadcast service from the base station.

In some embodiments, performing the broadcast service management may comprise: in the case that the user equipment determines, based on the configuration information, to receive the broadcast service, receiving the broadcast service from the base station; and monitoring an MCCH corresponding to the broadcast service.

In some embodiments, performing the broadcast service management may comprise: in the case that the user equipment determines, based on the configuration information, not to receive the broadcast service, refraining from receiving the broadcast service from the base station; and refraining from monitoring an MCCH corresponding to the broadcast service.

In some embodiments, the configuration information may comprise a parameter associated with an area of the broadcast service, and determining whether to receive the broadcast service may comprise: determining whether a criterion indicated by the parameter is fulfilled.

In some embodiments, the parameter may comprise one of the following: a reference location and a radius; or more than one location. In some embodiments, the criterion may comprise the user equipment being in the area indicated by the parameter.

In some embodiments, the parameter may comprise one of the following: an identity of a beam in a serving cell of the NTN; an identity of an RAN notification area; an angle threshold for an angle between the user equipment and a satellite that provides the serving cell; a first time threshold for a propagation delay between the user equipment and the satellite or the base station; or a second time threshold for a timing advance between the user equipment and the satellite or the base station.

In some embodiments, the criterion may comprise one of the following: the user equipment selects the beam indicated by the identity of the beam; the user equipment is in the RAN notification area; the angle between the user equipment and the satellite is smaller or larger than the angle threshold; the propagation delay is smaller or larger than the first time threshold; or the timing advance is smaller or larger than the second time threshold.

In some embodiments, the configuration information may comprise an indication of whether the user equipment receives the broadcast service from the base station, and determining whether to receive the broadcast service may comprise: determining whether the indication indicates the user equipment to receive the broadcast service. In some embodiments, the first configuration may further comprise a validity duration for the indication.

In some embodiments, the first configuration may comprise a stop serving time or a feeder link switch time of at least one neighbor cell in the NTN that supports the broadcast service.

In some embodiments, the method 600 may further include: determining a frequency priority for the broadcast service based on the stop serving time or the feeder link switch time of the at least one neighbor cell.

In some embodiments, determining the frequency priority for the broadcast service may comprise: restricting to consider a frequency to be the highest priority during a broadcast session of the broadcast service, in the case that a condition is fulfilled.

In some embodiments, the condition may comprise one of the following: the at least one neighbor cell using the frequency is approaching the stop serving time or the feeder link switch time; remaining time before the stop serving time or the feeder link switch time is less than a threshold; or remaining time before the stop serving time or the feeder link switch time is less than an expected reception duration of the broadcast service at the user equipment.

In some embodiments, the method 600 may further include: applying an offset to a parameter value for a cell reselection based on the stop serving time or the feeder link switch time.

In some embodiments, applying the offset to the parameter value for the cell reselection may comprise at least one of the following: applying an RSRP offset to an RSRP threshold for the cell reselection; applying an RSRQ offset to an RSRQ threshold for the cell reselection; or applying a time offset to a time threshold for the cell reselection.

In some embodiments, the cell reselection may comprise one of the following: a non-equal inter-frequency cell reselection; an inter-RAT cell reselection; an intra-frequency cell reselection; or an equal priority inter-frequency cell reselection. In some embodiments, the offset may be associated with remaining time before the stop serving time or the feeder link switch time.

In some embodiments, the method 600 may further include: receiving the stop serving time or the feeder link switch time in one of the following: an SIB2 associated with the at least one neighbor cell; an SIB19 associated with the at least one neighbor cell; an SIB20 associated with an MBS configuration for broadcast or part of the MBS configuration for broadcast; an SIB21 associated with a frequency or a FSAI; or dedicated signaling.

In some embodiments, the first configuration may comprise an indication of acquiring an MCCH configuration in the case that the user equipment does not receive an MCCH change notification at an MCCH modification period boundary.

In some embodiments, the method 600 may further include: acquiring an MCCH configuration on one of the following conditions: after a GNSS measurement is complete; after a GNSS measurement is complete, in the case that a corresponding measurement duration covers the MCCH modification period boundary; after GNSS measurements is complete, in the case that the MCCH change notification is received in a network response for GNSS result reporting; after acquiring SIB19 is complete; after acquiring SIB19 is complete, in the case that a corresponding acquiring duration covers the MCCH modification period boundary; or after acquiring SIB19 is complete, in the case that the MCCH change notification is received in the acquired SIB19.

FIG. 7 illustrates a flowchart of a method 700 that supports performing PUSCH retransmissions in accordance with aspects of the present disclosure. The operations of the method 700 may be implemented by a device or its components as described herein. For example, the operations of the method 700 may be performed by the base station 102 as described herein. In some implementations, the device may execute a set of instructions to control the function elements of the device to perform the described functions. Additionally, or alternatively, the device may perform aspects of the described functions using special-purpose hardware.

At block 705, the method may include determining a first configuration for a broadcast service in an NTN. The operations of determining the first configuration may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of determining the first configuration may be performed by a device as described with reference to FIG. 1A.

At block 710, the method may include transmitting the first configuration to a user equipment. The operations of transmitting the first configuration may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of transmitting the first configuration may be performed by a device as described with reference to FIG. 1A.

In some embodiments, the configuration information may comprise a parameter associated with an area of the broadcast service. In some embodiments, the parameter may comprise one of the following: a reference location and a radius; or more than one location.

In some embodiments, the configuration information may comprise an indication of whether the user equipment receives the broadcast service from the base station. In some embodiments, the first configuration may further comprise a validity duration for the indication.

In some embodiments, the method 700 may further include: transmitting the stop serving time or the feeder link switch time in one of the following: an SIB2 associated with the at least one neighbor cell; an SIB19 associated with the at least one neighbor cell; an SIB20 associated with an MBS configuration for broadcast or part of the MBS configuration for broadcast; an SIB21 associated with a frequency or a FSAI; or dedicated signaling.

In some embodiments, the indication may indicate the user equipment to acquire an MCCH configuration on one of the following conditions: after a GNSS measurement is complete; after a GNSS measurement is complete, in the case that a corresponding measurement duration covers the MCCH modification period boundary; after GNSS measurements is complete, in the case that the MCCH change notification is received in a network response for GNSS result reporting; after acquiring SIB19 is complete; after acquiring SIB19 is complete, in the case that a corresponding acquiring duration covers the MCCH modification period boundary; or after acquiring SIB19 is complete, in the case that the MCCH change notification is received in the acquired SIB19.

It should be noted that the methods described herein describes possible implementations, and that the operations and the steps may be rearranged or otherwise modified and that other implementations are possible. Further, aspects from two or more of the methods may be combined.

The various illustrative blocks and components described in connection with the disclosure herein may be implemented or performed with a general-purpose processor, a DSP, an ASIC, a CPU, an FPGA or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general-purpose processor may be a microprocessor, but in the alternative, the processor may be any processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices (e.g., a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration.

The functions described herein may be implemented in hardware, software executed by a processor, firmware, or any combination thereof. If implemented in software executed by a processor, the functions may be stored on or transmitted over as one or more instructions or code on a computer-readable medium. Other examples and implementations are within the scope of the disclosure and appended claims. For example, due to the nature of software, functions described herein may be implemented using software executed by a processor, hardware, firmware, hardwiring, or combinations of any of these. Features implementing functions may also be physically located at various positions, including being distributed such that portions of functions are implemented at different physical locations.

Computer-readable media includes both non-transitory computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. A non-transitory storage medium may be any available medium that may be accessed by a general-purpose or special-purpose computer. By way of example, non-transitory computer-readable media may include RAM, ROM, electrically erasable programmable ROM (EEPROM) , flash memory, compact disk (CD) ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other non-transitory medium that may be used to carry or store desired program code means in the form of instructions or data structures and that may be accessed by a general-purpose or special-purpose computer, or a general-purpose or special-purpose processor.

As used herein, including in the claims, an article “a” before an element is unrestricted and understood to refer to “at least one” of those elements or “one or more” of those elements. The terms “a, ” “at least one, ” “one or more, ” and “at least one of one or more” may be interchangeable. As used herein, including in the claims, “or” as used in a list of items (e.g., a list of items prefaced by a phrase such as “at least one of” or “one or more of” or “one or both of” ) indicates an inclusive list such that, for example, a list of at least one of A, B, or C means A or B or C or AB or AC or BC or ABC (i.e., A and B and C) . Also, as used herein, the phrase “based on” shall not be construed as a reference to a closed set of conditions. For example, an example step that is described as “based on condition A” may be based on both a condition A and a condition B without departing from the scope of the present disclosure. In other words, as used herein, the phrase “based on” shall be construed in the same manner as the phrase “based at least in part on. Further, as used herein, including in the claims, a “set” may include one or more elements.

The description herein is provided to enable a person having ordinary skill in the art to make or use the disclosure. Various modifications to the disclosure will be apparent to a person having ordinary skill in the art, and the generic principles defined herein may be applied to other variations without departing from the scope of the disclosure. Thus, the disclosure is not limited to the examples and designs described herein but is to be accorded the broadest scope consistent with the principles and novel features disclosed herein.

Claims

A user equipment, comprising:

a processor; and

a transceiver coupled to the processor,

wherein the processor is configured to:

receive from a base station, via the transceiver, a first configuration for a broadcast service in a non-terrestrial network (NTN) ; and

perform broadcast service management based on the first configuration.
The user equipment of claim 1, wherein the first configuration comprises configuration information for the user equipment to determine whether to receive the broadcast service from the base station.
The user equipment of claim 2, wherein performing the broadcast service management comprises:

in the case that the user equipment determines, based on the configuration information, to receive the broadcast service, receiving the broadcast service from the base station; and

monitoring a Multicast and Broadcast Services (MBS) Control Channel (MCCH) corresponding to the broadcast service.
The user equipment of claim 2, wherein the configuration information comprises a parameter associated with an area of the broadcast service, and determining whether to receive the broadcast service comprises:

determining whether a criterion indicated by the parameter is fulfilled.
The user equipment of claim 4, wherein the parameter comprises one of the following:

a reference location and a radius; or

more than one location.
The user equipment of claim 5, wherein the criterion comprises the user equipment being in the area indicated by the parameter.
The user equipment of claim 4, wherein the parameter comprises one of the following:

an identity of a beam in a serving cell of the NTN;

an identity of a radio access network (RAN) notification area;

an angle threshold for an angle between the user equipment and a satellite that provides the serving cell;

a first time threshold for a propagation delay between the user equipment and the satellite or the base station; or

a second time threshold for a timing advance between the user equipment and the satellite or the base station.
The user equipment of claim 7, wherein the criterion comprises one of the following:

the user equipment selects the beam indicated by the identity of the beam;

the user equipment is in the RAN notification area;

the angle between the user equipment and the satellite is smaller or larger than the angle threshold;

the propagation delay is smaller or larger than the first time threshold; or

the timing advance is smaller or larger than the second time threshold.
The user equipment of claim 1, wherein the first configuration comprises a stop serving time or a feeder link switch time of at least one neighbor cell in the NTN that supports the broadcast service.
The user equipment of claim 9, wherein the processor is configured to:

determine a frequency priority for the broadcast service based on the stop serving time or the feeder link switch time of the at least one neighbor cell.
The user equipment of claim 9, wherein the processor is configured to:

apply an offset to a parameter value for a cell reselection based on the stop serving time or the feeder link switch time.
The user equipment of claim 1, wherein the first configuration comprises an indication of acquiring an MCCH configuration in the case that the user equipment does not receive an MCCH change notification at an MCCH modification period boundary.
The user equipment of claim 12, wherein the processor is configured to acquire an MCCH configuration on one of the following conditions:

after a global navigation satellite system (GNSS) measurement is complete;

after a GNSS measurement is complete, in the case that a corresponding measurement duration covers the MCCH modification period boundary;

after GNSS measurements is complete, in the case that the MCCH change notification is received in a network response for GNSS result reporting;

after acquiring SIB19 is complete;

after acquiring SIB19 is complete, in the case that a corresponding acquiring duration covers the MCCH modification period boundary; or

after acquiring SIB19 is complete, in the case that the MCCH change notification is received in the acquired SIB19.
A base station, comprising:

a processor; and

a transceiver coupled to the processor,

wherein the processor is configured to:

determine a first configuration for a broadcast service in a non-terrestrial network (NTN) ; and

transmit to a user equipment, via the transceiver, the first configuration.
The base station of claim 14, wherein the first configuration comprises configuration information for the user equipment to determine whether to receive the broadcast service from the base station.
The base station of claim 15, wherein the configuration information comprises a parameter associated with an area of the broadcast service.
The base station of claim 14, wherein the first configuration comprises a stop serving time or a feeder link switch time of at least one neighbor cell in the NTN that supports the broadcast service.
The base station of claim 14, wherein the first configuration comprises an indication indicating the user equipment to acquire an MCCH configuration on one of the following conditions:

after a global navigation satellite system (GNSS) measurement is complete;

after a GNSS measurement is complete, in the case that a corresponding measurement duration covers the MCCH modification period boundary;

after GNSS measurements is complete, in the case that the MCCH change notification is received in a network response for GNSS result reporting;

after acquiring SIB19 is complete;

after acquiring SIB19 is complete, in the case that a corresponding acquiring duration covers the MCCH modification period boundary; or

after acquiring SIB19 is complete, in the case that the MCCH change notification is received in the acquired SIB19.
A method performed by a user equipment, comprising:

receiving, from a base station, a first configuration for a broadcast service in a non-terrestrial network (NTN) ; and

performing broadcast service management based on the first configuration.
A method performed by a base station, comprising:

determining a first configuration for a broadcast service in a non-terrestrial network (NTN) ; and

transmitting, to a user equipment, the first configuration.