Method and apparatus for scheduling multicast broadcast service in nr system

Abstract

The application provides a scheduling method and device for multicast broadcast service in an NR system. The method comprises the following steps: a gNB configures a plurality of MBS channels (MCH) for an SFN area, determines MBS sessions carried on each MCH, configures a physical MBS channel (PMCH) for each MCH, and configures a resource pool for each PMCH; for each PMCH, the gNB schedules resources in the resource pool of the PMCH in each scheduling period of the PMCH, and transmits data of each MBS session on the MCH corresponding to the PMCH through the scheduled resources. The application solves the problem of how to schedule multicast broadcast service in the SFN mode.

Description

Technical Field

[0001] This application relates to communication technology, and more particularly to a scheduling method and device for multicast services in an NR system. Background Technology

[0002] Currently, to improve the reception quality of Multicast / Broadcast Service (MBS) sessions, a Single Frequency Network (SFN) can be used to transmit MBS sessions in a point-to-multipoint (PTM) manner. Specifically, in a New Radio Access (NR) system with co-frequency networking, for MBS sessions transmitted simultaneously by various cells within an area, each cell uses the same time-frequency resources to transmit the same MBS session data in PTM mode at the same time, generating the same MBS signal. For user equipment (UE) receiving this MBS session in PTM mode, the signals from different cells are multipath signals of the same signal, which can be combined to improve the reception quality of the MBS session.

[0003] However, when sending MBS sessions in the above-mentioned SFN method, how to configure resources for MBS sessions and how to schedule MBS sessions on the configured resources are problems that need to be solved. Therefore, there is an urgent need for a method and device that can schedule MBS sessions. Summary of the Invention

[0004] This application provides a scheduling method and device for multicast broadcast services in an NR system, which solves the technical problem of how to schedule multicast broadcast services in SFN mode.

[0005] In a first aspect, this application provides a scheduling method for multicast services in an NR system, applied to a next-generation radio access network (gNB), the method comprising:

[0006] The gNB configures a Common Frequency Resource (CFR) for an SFN area and determines the configuration information of the CFR. The CFR of the SFN area consists of several consecutive Common Resource Blocks (CRBs) in the entire bandwidth of the carrier frequency used by the SFN area. Each cell in the SFN area uses the CFR configured for the SFN area to send various MBS sessions of the SFN area.

[0007] Based on a list of MBS sessions transmitted in SFN mode within the SFN area, the gNB configures several MBS channels (MCHs) for the SFN area, determines the MBS sessions carried on each MCH, and the MCH is a dedicated transmission channel for MBS sessions in the SFN area. For each MCH, the gNB determines the configuration information of each MBS session carried on the MCH and generates a list of MBS session configuration information for the MCH. The gNB configures a physical MBS channel (PMCH) for each MCH, and the PMCH is a dedicated physical channel for MBS sessions in the SFN area. The data of the MBS sessions carried on each MCH is mapped to the PMCH configured for the MCH.

[0008] The gNB selects one MCH from the configured MCHs for transmitting a transport block (TB) from the MBS Control Channel (MCCH) of the SFN area.

[0009] The gNB configures a periodically occurring resource pool for each PMCH on the CFR in the SFN area, determines the scheduling period of each PMCH and the mapping method between time slots and beams within the scheduling period, and determines the configuration information of each PMCH.

[0010] For each PMCH, gNB schedules the PMCH in each scheduling cycle and generates MBS scheduling information MAC CE for each scheduling cycle based on the scheduling results;

[0011] For each PMCH, within each scheduling period, the gNB generates a set of TBs based on the MBS scheduling information MAC CE of that scheduling period, using the data of each MBS session carried on the MCH corresponding to the PMCH. It then determines a set of PMCH time slots within that scheduling period based on the index of the time slot-beam mapping method, and transmits the set of TBs through the set of PMCH time slots.

[0012] Furthermore, for each PMCH, the gNB schedules the PMCH within each scheduling cycle of that PMCH, and generates MBS scheduling information MAC CE for each scheduling cycle based on the scheduling results, including:

[0013] For a PMCH, when the gNB configures a data MCS for the PMCH, the data MCS is used when scheduling the MTCH of each MBS session carried on the MCH corresponding to the PMCH; when the gNB configures multiple data MCSs for the PMCH, the gNB configures a data MCS for the MTCH of each MBS session carried on the MCH corresponding to the PMCH, and configures a data MCS for the MBS scheduling information MAC CE.

[0014] For the current scheduling period of the PMCH, the gNB assigns PMCH slot numbers that can be used to send various MBS sessions within the current scheduling period in chronological order, starting from 0. Then, based on the data MCS configured for the MBS scheduling information MAC CE, the gNB reserves one PMCH slot or multiple consecutive PMCH slots for the MBS scheduling information MAC CE within the current scheduling period, starting from slot 0, for priority transmission of the MBS scheduling information MAC CE within the current scheduling period.

[0015] The gNB determines the starting time slot for scheduling each MBS session within the current scheduling cycle.

[0016] The gNB schedules each MBS session sequentially within the current scheduling period, starting from the initial time slot, until all MBS sessions have been scheduled or the resources in the PMCH resource pool have been allocated within the current scheduling period.

[0017] Furthermore, the gNB sequentially schedules each MBS session within the current scheduling period, starting from the initial time slot, until all MBS sessions have been scheduled or the resources in the PMCH resource pool have been allocated within the current scheduling period, including:

[0018] gNB uses one of the following methods to determine the scheduling order of each MBS session within the current scheduling period:

[0019] Method 1: If the data network has configured a priority for each MBS session, then the MBS sessions are scheduled sequentially from highest to lowest priority until all PMCH time slots in the current scheduling period are allocated or all MBS sessions are scheduled. For MBS sessions with the same priority, the PMCH time slots already allocated in the current scheduling period are excluded. If the remaining PMCH time slots in the current scheduling period are sufficient to transmit the data of these MBS sessions, then the MBS sessions are scheduled sequentially. If the remaining PMCH time slots in the current scheduling period are insufficient to transmit the data of these MBS sessions, then these MBS sessions can be randomly sorted or sorted according to the time order in which they were established, and then the MBS sessions are scheduled sequentially until all remaining PMCH time slots in the current scheduling period are allocated.

[0020] Method 2: If the data network configures a priority for each MBS session, then the MBS sessions are scheduled sequentially from highest to lowest priority until the PMCH time slots in the current scheduling period are fully allocated or all MBS sessions are scheduled. For MBS sessions with the same priority, the PMCH time slots already allocated in the current scheduling period are excluded. If the remaining PMCH time slots in the current scheduling period are sufficient to transmit the data of these MBS sessions, the MBS sessions are scheduled sequentially. If the remaining PMCH time slots in the current scheduling period are insufficient to transmit the data of these MBS sessions, the remaining PMCH time slots in the current scheduling period can be evenly distributed to these MBS sessions, or the remaining PMCH time slots in the current scheduling period can be used to evenly transmit the data of these MBS sessions. For each MBS session, the data on each MTCH of the MBS session is transmitted sequentially in ascending order of data MCS and then in ascending order of logical channel ID until the PMCH time slots allocated to the MBS session are used up or the amount of data allocated to the MBS session is used up. Then, the scheduling of PMCH in the current scheduling period ends.

[0021] Method 3: If the data network does not configure priority for each MBS session, then the MBS sessions are randomly sorted or sorted according to the establishment time of each MBS session, and the MBS sessions are scheduled in sequence until the PMCH time slots in the current scheduling period are allocated or all MBS sessions are scheduled.

[0022] Method 4: If the data network does not assign priority to each MBS session, and if there are enough PMCH time slots available for transmitting data of each MBS session starting from the start time slot in the current scheduling period, then the MBS sessions are randomly sorted or sorted according to the establishment time order of each MBS session, and scheduled sequentially. Otherwise, the PMCH time slots starting from the start time slot in the current scheduling period are evenly distributed to each MBS session, or all PMCH time slots starting from the start time slot in the current scheduling period are used to evenly transmit the data of these MBS sessions: For each MBS session, the data on each MTCH of the MBS session is transmitted sequentially in ascending order of data MCS and then in ascending order of logical channel ID until the PMCH time slots allocated to the MBS session are used up or the amount of data allocated to the MBS session is used up, and then the scheduling of PMCH in the current scheduling period ends.

[0023] Then, gNB schedules each MBS session sequentially.

[0024] Furthermore, the gNB schedules each MBS session sequentially, including:

[0025] When scheduling each MBS session, the gNB centrally allocates several consecutive PMCH time slots on each MTCH of the MBS session to carry the data of the MBS session.

[0026] When the last PMCH slot allocated to an MBS session is not filled with data from that MBS session, the gNB schedules the next MBS session starting from that slot; otherwise, the gNB schedules the next MBS session starting from the next PMCH slot.

[0027] When scheduling each MBS session, if the MTCH of the MBS session uses the same data MCS, the MTCHs are scheduled in ascending order of logical channel ID; if the MTCHs of the MBS session do not use the same data MCS, the MTCHs are scheduled in ascending order of data MCS first and then in ascending order of logical channel ID.

[0028] When scheduling an MTCH, if the data on the MTCH cannot fill a PMCH time slot, the next MTCH is scheduled starting from the PMCH time slot; when multiple MTCHs are scheduled simultaneously in a PMCH time slot, the data on these MTCHs is scheduled according to the smallest data MCS among the data MCS of these MTCHs; these MTCHs can be MTCHs of the same MBS session or MTCHs of different MBS sessions.

[0029] For each allocated PMCH time slot, the gNB determines the MCS used when transmitting the corresponding TB in the PMCH time slot: when only one MTCH is scheduled in the PMCH time slot, the MCS used when transmitting the corresponding TB in the PMCH time slot is the data MCS of the MTCH; otherwise, the MCS used when transmitting the corresponding TB in the PMCH time slot is the smallest data MCS among the data MCS of each MTCH scheduled in the PMCH time slot.

[0030] Furthermore, the gNB generates MBS scheduling information MAC CE for the current scheduling period based on the scheduling result of the current scheduling period, including:

[0031] The MBS scheduling information MAC CE provides a list of MBS sessions, which provides:

[0032] (1) ID of each scheduled MBS session: TMGI;

[0033] (2) The number of PMCH time slots occupied by each scheduled MBS session;

[0034] (3) The MCS used when sending the corresponding TB in each PMCH time slot occupied by each scheduled MBS session.

[0035] Furthermore, for each PMCH, the gNB schedules the PMCH within each scheduling cycle of that PMCH, and generates MBS scheduling information MAC CE for each scheduling cycle based on the scheduling results, including:

[0036] For a PMCH, the gNB determines each MRB of each MBS session carried on the MCH corresponding to the PMCH, determines the QoS requirements of each MRB based on the QoS requirements of each QoS flow carried on each MRB, divides all MRBs into several groups, each group consisting of several MRBs with the same or similar QoS requirements, configures a data MCS for each group of MRBs, and uses the data MCS configured for that group of MRBs when transmitting data on the MTCH corresponding to each MRB in that group of MRBs; configures a data MCS for the MBS scheduling information MAC CE.

[0037] For the current scheduling period of the PMCH, the gNB assigns PMCH slot numbers that can be used to send various MBS sessions within the current scheduling period in chronological order, starting from 0. Then, based on the data MCS configured for the MBS scheduling information MAC CE, the gNB reserves one PMCH slot or multiple consecutive PMCH slots for the MBS scheduling information MAC CE within the current scheduling period, starting from slot 0, for priority transmission of the MBS scheduling information MAC CE within the current scheduling period.

[0038] The gNB determines the starting time slot for scheduling each MBS session within the current scheduling cycle.

[0039] The gNB starts from the initial time slot and schedules each MRB group sequentially within the current scheduling period until the scheduling of all MRB groups is completed or the time slots in the PMCH resource pool are allocated within the current scheduling period.

[0040] The gNB generates MBS scheduling information MACCE for the current scheduling period based on the scheduling result of the current scheduling period.

[0041] Furthermore, the gNB, starting from the initial time slot, sequentially schedules each MRB group within the current scheduling period until the scheduling of all MRB groups is completed or the time slot allocation within the PMCH resource pool is completed within the current scheduling period, including:

[0042] Before scheduling the MBS sessions carried on the MCH corresponding to the PMCH in the current scheduling cycle, the gNB needs to perform admission control on each MBS session according to the following method:

[0043] If there are sufficient resources to transmit data for each MBS session within the current scheduling period, then all MBS sessions can be scheduled within the current scheduling period; otherwise, within the current scheduling period, resources are allocated to each MBS session in descending order of priority, starting with the MBS session with the highest priority, until all resources within the current scheduling period are allocated; for the last MBS session scheduled, resources are allocated to the MRBs with high QoS requirements of that MBS session first, and each scheduled MBS session is recorded; for the last MBS session scheduled, if only some of the MRBs in all the MRBs of that MBS session are scheduled, each scheduled MRB of that MBS session is recorded.

[0044] After admission control is applied to each MBS session, the gNB schedules each MRB group in ascending order of data MCS. When scheduling each MRB group, only the MTCH corresponding to the recorded MBS session or the MTCH corresponding to the recorded MRB is scheduled from the MTCH ID list of the MRB group.

[0045] Further, the step of scheduling only the MTCH corresponding to the recorded MBS session or the MTCH corresponding to the recorded MRB in the MTCH ID list corresponding to the MRB group when scheduling each MRB group includes:

[0046] The gNB schedules each MRB group in ascending order of data MCS. When scheduling each MRB group, it first determines the MTCH corresponding to each recorded MBS session and the MTCH corresponding to each recorded MRB in the MTCH ID list corresponding to the MRB group. For all determined MTCHs, these MTCHs are scheduled in ascending order of MTCH ID. When scheduling these MTCHs, the gNB allocates one or more PMCH time slots to each scheduled MTCH according to the data MCS configured for the MRB group for transmitting data on the MTCH. When the last time slot allocated to the MTCH is not filled by the data on the MTCH, the next MTCH is scheduled starting from the PMCH time slot.

[0047] When multiple MTCHs are scheduled simultaneously in a PMCH time slot, the data MCS used when scheduling these MTCHs in that PMCH time slot is the smallest data MCS among the data MCS used in the MRB group to which these MTCHs belong.

[0048] At the end of scheduling, the gNB determines each scheduled MRB group. For each scheduled MRB group, the gNB determines the total number of PMCH slots allocated to all scheduled MTCHs in the MTCH ID list corresponding to that MRB group. For each allocated PMCH slot, the gNB determines the MCS used when transmitting the corresponding TB in that PMCH slot: when only one MTCH is scheduled in that PMCH slot, the MCS used when transmitting the corresponding TB in that slot is the data MCS used by the MRB group corresponding to that MTCH; when multiple MTCHs are scheduled in that slot, the MCS used when transmitting the corresponding TB in that slot is the smallest data MCS among the data MCS used by the MRB groups corresponding to these scheduled MTCHs.

[0049] Furthermore, the gNB, starting from the initial time slot, sequentially schedules each MRB group within the current scheduling period until the scheduling of all MRB groups is completed or the time slot allocation within the PMCH resource pool is completed within the current scheduling period, including:

[0050] gNB schedules each MRB group in ascending order of data MCS until all MRB groups have been scheduled or the PMCH time slots in the current scheduling period have been allocated.

[0051] When scheduling each MRB group, each MTCH in the MTCH ID list corresponding to the MRB group is scheduled in ascending order of MTCH ID; when the PMCH slot allocated to an MTCH is not full, the next MTCH is scheduled starting from that PMCH slot; if a PMCH slot transmits data on multiple MTCHs at the same time, the data MCS used when transmitting data on these MTCHs is the smallest data MCS among the data MCS used by the MRB groups corresponding to these MTCHs;

[0052] At the end of scheduling, the gNB determines the ID of each scheduled MRB group. For each scheduled MRB group, the gNB determines the total number of PMCH slots allocated to all scheduled MTCHs in the MTCH ID list corresponding to that MRB group. For each allocated PMCH slot, the gNB determines the MCS used when transmitting the corresponding TB in that PMCH slot: when only one MTCH is scheduled in that PMCH slot, the MCS used when transmitting the corresponding TB in that slot is the data MCS used by the MRB group corresponding to that MTCH; when multiple MTCHs are scheduled in that slot, the MCS used when transmitting the corresponding TB in that slot is the smallest data MCS among the data MCS used by the MRB groups corresponding to these scheduled MTCHs.

[0053] Furthermore, the gNB, starting from the initial time slot, sequentially schedules each MRB group within the current scheduling period until the scheduling of all MRB groups is completed or the time slot allocation within the PMCH resource pool is completed within the current scheduling period, including:

[0054] The gNB schedules each MRB group in ascending order of data MCS. When scheduling an MRB group, the PMCH time slots already allocated in the current scheduling period are excluded. If the remaining PMCH time slots in the current scheduling period are sufficient to transmit the data on each MTCH in the MTCH ID list corresponding to the MRB group, the MTCHs are scheduled in ascending order of MTCH ID. If the remaining PMCH time slots in the current scheduling period are insufficient to transmit the data on each MTCH in the MTCH ID list corresponding to the MRB group, the remaining PMCH time slots are used to evenly transmit the data on each MTCH in the MTCH ID list corresponding to the MRB group.

[0055] When the time slot allocated to an MTCH is not filled by the data on that MTCH, the next MTCH is scheduled starting from that PMCH time slot; when multiple MTCHs are scheduled in a PMCH time slot at the same time, the data MCS used when scheduling these MTCHs in that PMCH time slot is the smallest data MCS among the data MCS used by the MRB groups corresponding to these MTCHs.

[0056] At the end of scheduling, the gNB determines the ID of each scheduled MRB group. For each scheduled MRB group, the gNB determines the total number of PMCH slots allocated to all scheduled MTCHs in the MTCH ID list corresponding to that MRB group. For each allocated PMCH slot, the gNB determines the MCS used when transmitting the corresponding TB in that PMCH slot: when only one MTCH is scheduled in that PMCH slot, the MCS used when transmitting the corresponding TB in that slot is the data MCS used by the MRB group corresponding to that MTCH; when multiple MTCHs are scheduled in that slot, the MCS used when transmitting the corresponding TB in that slot is the smallest data MCS among the data MCS used by the MRB groups corresponding to these scheduled MTCHs.

[0057] Furthermore, the gNB generates MBS scheduling information MAC CE for the current scheduling period based on the scheduling result of the current scheduling period, including:

[0058] The MBS scheduling information MAC CE provides an MRB group list, which provides:

[0059] (1) ID of each scheduled MRB group:

[0060] (2) The number of PMCH slots allocated by gNB to each scheduled MRB group, that is: the number of PMCH slots allocated by gNB to each MTCH in the MTCH ID list corresponding to the MRB group.

[0061] (3) The MCS used when transmitting the corresponding TB in each PMCH time slot allocated to each scheduled MRB group.

[0062] Furthermore, for each PMCH, the configuration information of the PMCH includes:

[0063] (1) Configuration information of CFR in the SFN area;

[0064] (2) The list of MBS session configuration information for the MCH corresponding to the PMCH;

[0065] (3) Configuration information of the PMCH resource pool: the period P of the resource pool, the initial radio frame offset SysFNOFFSET of the resource pool in each period, the initial time slot index TSOFFSET, the PMCH time slot configuration information, the PMCH time domain resource configuration information, the physical layer parameters used by the PMCH, the PMCH DMRS configuration information, the PMCH PTRS configuration information, the at least one data MCS used by the PMCH, the number of repeated transmissions R for each TB on the PMCH, and the N beams used when transmitting each TB.

[0066] (4) The scheduling period T of the PMCH and the subscript of the mapping method between time slots and beams within the scheduling period of the PMCH;

[0067] (5) Configuration information of the scheduling strategy adopted by PMCH.

[0068] Furthermore, the configuration information of each MBS session in the MBS session configuration information list corresponding to the PMCH includes:

[0069] (1) MBS session ID: TMGI;

[0070] (2) Service Data Adaptation Protocol (SDAP) configuration information for MBS session: gNB configures an SDAP entity for the MBS session based on this information, which is used to map the QoS stream of the MBS session to one or more MBS Radio Bearers (MRBs).

[0071] (3) Packet Data Convergence Protocol (PDCP) configuration information for each MRB of the MBS session: gNB configures a PDCP entity for each MRB of the MBS session based on this information;

[0072] (4) Radio Link Control (RLC) configuration information for each MRB of the MBS session: The gNB configures an Unacknowledged Mode (UM) RLC entity for each MRB of the MBS session based on this information;

[0073] (5) MBS Traffic Channel (MTCH) configuration information of MBS session: gNB configures an MTCH for each MRB of the MBS session and determines the ID of each MTCH. The MTCH configuration information of the MBS session consists of the IDs of each MTCH of the MBS session.

[0074] Furthermore, the mapping method between time slots and beams within the scheduling period of the PMCH includes:

[0075] First, gNB assigns PMCH slot numbers, starting from 0 and in chronological order, to the PMCH slots that can be used to send various MBS sessions within the current scheduling period.

[0076] Then, gNB generates S TBs based on the MBS scheduling information MAC CE of the current scheduling period and the data on each MTCH of each MBS session on the MCH corresponding to the PMCH, and determines the MCS used by each TB. S is the total number of PMCH slots allocated to the PMCH in the MBS scheduling information MAC CE of the current scheduling period.

[0077] According to the repetition count R of each TB in the configuration information of the PMCH and the N beams used when transmitting each TB in the configuration information of the PMCH, the gNB occupies the first S*R*N time slots in the current scheduling period to transmit the S TBs through the PMCH.

[0078] When the gNB occupies the first S*R*N time slots in the current scheduling period and transmits the S TBs through the PMCH, the beam used to transmit the PMCH and the TB carried on the PMCH in each occupied PMCH time slot are determined according to one of the following PMCH time slot to beam mapping methods:

[0079] (1) Mapping method 0:

[0080] The S*R*N time slots can be divided into S groups, each group containing N*R consecutive time slots, and the S TBs can be transmitted through the S groups; further, the N*R time slots in each group can be divided into R subgroups, each subgroup containing N consecutive time slots, and the corresponding TBs can be repeatedly transmitted R times through the R subgroups, and the corresponding TBs can be transmitted once in different beam directions within the N time slots in each subgroup;

[0081] (2) Mapping method 1:

[0082] The S*R*N time slots can be divided into S groups, each containing N*R time slots, and the S TBs can be transmitted through the S groups; further, the N*R time slots in each group can be divided into N subgroups, each subgroup containing R consecutive time slots, and the corresponding TBs can be transmitted in N beam directions through the N subgroups respectively; within each subgroup, the corresponding TBs can be transmitted R times in the same beam direction through the R time slots;

[0083] (3) Mapping method 2:

[0084] The S*R*N time slots can be divided into R groups, each group containing N*S time slots, and the S TBs can be repeatedly transmitted R times through the R groups; further, the N*S time slots in each group can be divided into S subgroups, each subgroup containing N consecutive time slots, and the S TBs can be transmitted through the S subgroups respectively; within each subgroup, the same TB can be transmitted once in different beam directions through N time slots;

[0085] (4) Mapping method 3:

[0086] The S*R*N time slots can be divided into R groups, each group containing N*S time slots, and the S TBs can be repeatedly transmitted R times through the R groups; further, the N*S time slots in each group can be divided into N subgroups, each subgroup containing S consecutive time slots, and the S TBs can be transmitted in N beam directions through the N subgroups respectively; within each subgroup, S TBs can be transmitted in the same beam direction through the S time slots respectively;

[0087] Based on the different mapping methods of time slots and beams within the above scheduling periods, the mapping method of PMCH time slots and beams within the scheduling period can be configured using one of the following methods:

[0088] Method 1: In the 3GPP NR protocol, the mapping method between PMCH time slots and beams within the PMCH scheduling cycle is fixed as: mapping method 0 / 1 / 2 / 3;

[0089] Method 2: Configure the mapping method between PMCH time slots and beams within the PMCH scheduling period using a pre-configuration method and a configuration method based on Radio Resource Control (RRC) signaling.

[0090] Secondly, this application provides an apparatus for implementing a scheduling method for multicast services in an NR system. The apparatus is a gNB, and the gNB includes the following functions:

[0091] The gNB configures a Common Frequency Resource (CFR) for an SFN area and determines the configuration information of the CFR. The CFR of the SFN area consists of several consecutive Common Resource Blocks (CRBs) in the entire bandwidth of the carrier frequency used by the SFN area. Each cell in the SFN area uses the CFR configured for the SFN area to send various MBS sessions of the SFN area.

[0092] The gNB configures several MBS channels (MCHs) for the SFN area based on a list of MBS sessions transmitted in SFN mode within the SFN area, and determines the MBS sessions carried on each MCH. Each MCH is a dedicated transmission channel for MBS sessions within the SFN area. For each MCH, the gNB determines the configuration information for each MBS session carried on the MCH and generates a list of MBS session configuration information for that MCH. The gNB configures a Physical MBS Channel (PMCH) for each MCH. Each PMCH is a dedicated physical channel for MBS sessions within the SFN area, and the data of the MBS sessions carried on each MCH is mapped to the PMCH configured for that MCH.

[0093] The gNB selects one MCH from the configured MCHs for transmitting a transport block (TB) from the MBS Control Channel (MCCH) of the SFN area.

[0094] The gNB configures a periodically occurring resource pool for each PMCH on the CFR of the SFN area, determines the scheduling period of each PMCH and the mapping method between time slots and beams within the scheduling period, and determines the configuration information of each PMCH.

[0095] For each PMCH, the gNB schedules the PMCH in each scheduling cycle of the PMCH and generates MBS scheduling information MAC CE for each scheduling cycle based on the scheduling results;

[0096] For each PMCH, within each scheduling period, the gNB generates a set of TBs based on the MBS scheduling information MACCE of that scheduling period, using the data of each MBS session carried on the MCH corresponding to the PMCH. It then determines a set of PMCH time slots within that scheduling period based on the index of the time slot-beam mapping method, and transmits the set of TBs through the set of PMCH time slots.

[0097] In summary, the scheduling method and device for multicast broadcast services in an NR system provided in this application solve the problem of scheduling multicast broadcast services. Attached Figure Description

[0098] The accompanying drawings, which are incorporated in and form a part of this specification, illustrate embodiments consistent with this disclosure and, together with the description, serve to explain the principles of this disclosure.

[0099] Figure 1 A flowchart illustrating a scheduling method for multicast broadcast services in an NR system provided in Embodiment 1 of this application;

[0100] Figure 2 This is a flowchart illustrating a PMCH scheduling method based on a time-division multiplexing scheduling strategy provided in Embodiment 2 of this application.

[0101] Figure 3 This is a flowchart illustrating a PMCH scheduling method based on radio bearer QoS requirements, provided in Embodiment 3 of this application.

[0102] The accompanying drawings have illustrated specific embodiments of this disclosure, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concepts of this disclosure to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0103] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this disclosure.

[0104] To improve the reception quality of Multicast / Broadcast Service (MBS) sessions, a Single Frequency Network (SFN) can be used to transmit MBS sessions in PTM mode. Specifically, in New Radio Access (NR) systems with co-frequency networking, for MBS sessions simultaneously transmitted by various cells within an area, each cell uses the same time-frequency resources to transmit the same MBS session data in PTM mode at the same time, generating the same MBS signal. For User Equipment (UE) receiving this MBS session in PTM mode, the signals from different cells are multipath signals of the same signal, which can be combined to improve the reception quality of the MBS session. However, when transmitting MBS sessions in SFN mode, how to configure resources for the MBS session and how to schedule the MBS session on the configured resources are problems that need to be solved. Therefore, a method for scheduling MBS sessions under SFN mode is urgently needed.

[0105] This application provides a scheduling method and device for multicast services in an NR system, which aims to solve the above-mentioned technical problems in the prior art.

[0106] The technical solution of this application and how the technical solution of this application solves the above-mentioned technical problems are described in detail below with specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments. The embodiments of this application will now be described with reference to the accompanying drawings.

[0107] Figure 1 This is a flowchart illustrating a scheduling method for multicast services in an NR system provided in Embodiment 1 of this application. Figure 1 As shown, the multicast / broadcast service scheduling method includes:

[0108] 101. The gNB configures a Common Frequency Resource (CFR) for an SFN area and determines the configuration information of the CFR. The CFR of the SFN area consists of several consecutive Common Resource Blocks (CRBs) in the entire bandwidth of the carrier frequency used by the SFN area. Each cell in the SFN area uses the CFR configured for the SFN area to send various MBS sessions of the SFN area.

[0109] The gNB configures a CFR for the SFN area based on the bandwidth requirements of the MBS sessions transmitted in the SFN area. The CFR consists of several consecutive CRBs within the carrier frequency bandwidth used by the SFN area. Each cell within the SFN area uses the CFR configured for the SFN area to transmit its respective MBS sessions. Specifically, the configuration information for the CFR of the SFN area includes the following:

[0110] (1) Frequency domain resource configuration information of the CFR: the position of the starting CRB of the CFR and the number of consecutive CRBs occupied by the CFR.

[0111] (2) The cyclic prefix (CP) type and sub-carrier spacing (SCS) adopted by the CFR

[0112] Optionally, when the SFN area is used only for transmitting broadcast sessions in SFN mode, all cells comprising the SFN area are uniformly configured with CORESET 0 / Initial Downlink BWP: all cells have the same CORESET 0 / Initial Downlink BWP. The CFR of the SFN area can be the uniformly configured CORESET 0 / Initial Downlink BWP, and the CP type and SCS used by the CFR of the SFN area are the same as those used by the uniformly configured CORESET 0 / Initial Downlink BWP. Alternatively, the CFR of the SFN area may include the uniformly configured CORESET 0 / Initial Downlink BWP, and the CP type and SCS used by the CFR of the SFN area are the same as those used by the uniformly configured CORESET 0 / Initial Downlink BWP.

[0113] Optionally, when the SFN area is used only for transmitting multicast sessions in SFN mode, several downlink BWPs are uniformly configured for all cells in the SFN area, and the CFR configured for the SFN area is located on a uniformly configured downlink BWP. This uniformly configured downlink BWP is the activated downlink BWP of the UE receiving the multicast session in the SFN area. The CP type and SCS used by the CFR in the SFN area are the same as those of the uniformly configured downlink BWP. Each cell in the SFN area uses the CFR to transmit the multicast session in the SFN area.

[0114] Optionally, when the SFN area is used only for transmitting multicast sessions in SFN mode, at least two downlink BWPs are uniformly configured for all cells in the SFN area. The CFR configured for the SFN area is located in the common area of ​​several uniformly configured downlink BWPs, and these uniformly configured downlink BWPs have the same CP type and SCS. For a UE receiving a multicast session in the SFN area, one of these uniformly configured downlink BWPs is the active downlink BWP for that UE. The CP type and SCS used by the CFR in the SFN area are the same as those of these uniformly configured downlink BWPs. Each cell in the SFN area uses the CFR to transmit the multicast session in the SFN area.

[0115] 102. Based on the list of MBS sessions transmitted in SFN mode within the SFN area, the gNB configures several MBS channels (MCH) for the SFN area, determines the MBS sessions carried on each MCH, and the MCH is a dedicated transmission channel for MBS sessions in the SFN area; for each MCH, the gNB determines the configuration information of each MBS session carried on the MCH and generates a list of MBS session configuration information for the MCH; the gNB configures a physical MBS channel (PMCH) for each MCH, and the PMCH is a dedicated physical channel for MBS sessions in the SFN area, and the data of the MBS sessions carried on each MCH is mapped to the PMCH configured for the MCH.

[0116] After configuring CFR for the SFN area, the gNB configures several MBS channels (MCH) for the SFN area according to the list of MBS sessions transmitted in SFN mode within the SFN area, and determines the MBS sessions carried on each MCH. The MCH is a dedicated transmission channel for MBS sessions in the SFN area.

[0117] Preferably, each MBS session type is configured with a separate MCH, and different types of MBS sessions are carried by different MCHs. MBS sessions of the same type are carried by the same MCH.

[0118] A list of MBS sessions transmitted via SFN within an SFN area includes the following information:

[0119] (1) Identification of each MBS session transmitted in SFN mode within the SFN area: Specifically, an MBS session can be identified by a Temporary Mobile Group Identity (TMGI);

[0120] (2) Quality of Service (QoS) information of each MBS session transmitted in SFN mode within the SFN area: gNB determines the configuration information of the MBS session based on the QoS information of each MBS session;

[0121] How the gNB obtains a list of MBS sessions transmitted in SFN mode within an SFN area is not the subject of this application and will not be elaborated upon here.

[0122] For each MCH, the gNB determines the configuration information of each MBS session carried on the MCH, and the detailed process of generating the MBS session configuration information list for the MCH is as follows:

[0123] Step 1: For any MBS session carried on the MCH, the gNB determines the configuration information of the MBS session.

[0124] The configuration information for an MBS session includes:

[0125] (1) MBS Session ID: TMGI

[0126] (2) Service Data Adaptation Protocol (SDAP) configuration information for MBS session: gNB configures an SDAP entity for the MBS session based on this information, which is used to map the QoS stream of the MBS session to one or more MBS Radio Bearers (MRBs).

[0127] (3) Packet Data Convergence Protocol (PDCP) configuration information for each MRB of the MBS session: gNB configures a PDCP entity for each MRB of the MBS session based on this information;

[0128] (4) Radio Link Control (RLC) configuration information for each MRB of the MBS session: Based on this information, the gNB configures an Unacknowledged Mode (UM) RLC entity for each MRB of the MBS session.

[0129] (5) MBS Traffic Channel (MTCH) configuration information for the MBS session: The gNB configures an MTCH for each MRB of the MBS session and determines the ID of each MTCH. The MTCH configuration information of the MBS session consists of the IDs of each MTCH of the MBS session.

[0130] Since the data of each MBS session on each MTCH carried on the same MCH is transmitted through the same MCH, the gNB assigns a different ID to the MTCH of each MRB of each MBS session in order to distinguish different MTCHs on the MCH.

[0131] Step 2: For the MCH, gNB generates a list of MBS session configuration information for the MCH.

[0132] In this step, for the MCH, the gNB generates an MBS session configuration information list for the MCH based on the configuration information of each MBS session carried on the MCH obtained in step 1. The list consists of the configuration information of each MBS session carried on the MCH.

[0133] 103. The gNB selects one MCH from the configured MCHs for transmitting transport blocks (TBs) from the MBS Control Channel (MCCH) of the SFN area.

[0134] 104. The gNB configures a periodically occurring resource pool for each PMCH on the CFR of the SFN area, determines the scheduling period of each PMCH and the mapping method between time slots and beams within the scheduling period, and determines the configuration information of each PMCH.

[0135] Specifically, the process by which gNB configures a periodically occurring resource pool for each PMCH is as follows:

[0136] For each PMCH, the gNB configures a periodically occurring resource pool on the CFR of the SFN area. Within each period, this resource pool consists of several PMCH time slots. Within each PMCH time slot, the PMCH utilizes all CRB resources on the CFR during transmission. The gNB determines the configuration information of the PMCH resource pool. Specifically, the configuration information of a PMCH resource pool includes the following:

[0137] (1) The period P of the resource pool, the initial radio frame offset SFNOFFSET of the resource pool, and the initial time slot index TSOFFSET

[0138] (2) PMCH slot configuration information

[0139] (3) PMCH time-domain resource configuration information

[0140] (4) Physical layer parameters of PMCH

[0141] (5) PMCH DMRS configuration information

[0142] (6) PMCH PTRS configuration information

[0143] (7) At least one data MCS used by the PMCH, the number of retransmissions per TB on the PMCH, and the beam used when transmitting each TB.

[0144] The usage of each parameter in the above PMCH resource pool configuration information is as follows:

[0145] Within each period of P radio frames, the starting radio frame number SysFN of the PMCH resource pool satisfies the following formula, with the starting time slot index TSOFFSET.

[0146] SysFN MOD T = SFNOFFSET

[0147] When all downlink slots in the PMCH resource pool are used for PMCH transmission in each cycle, the PMCH slot configuration information of the PMCH resource pool includes the parameter DURATION, which is the number of downlink slots included in the PMCH resource pool.

[0148] When not all downlink slots in the PMCH resource pool are used for PMCH transmission in each period, the PMCH slot configuration information of the PMCH resource pool includes a parameter W and a bit sequence of length W. W represents the number of downlink slots in the PMCH resource pool in each period. The bit sequence of length W indicates which of the W downlink slots in the PMCH resource pool are used for PMCH transmission in each period. From left to right, the W bits of the bit sequence correspond to the first to the Wth downlink slots in the PMCH resource pool in each period. When the corresponding bit is 1, it indicates that the corresponding downlink slot is used for PMCH transmission; otherwise, the corresponding downlink slot is not used for PMCH transmission.

[0149] Within each PMCH time slot, when transmitting the PMCH, the gNB uses a set of consecutive OFDM symbols indicated by the PMCH time-domain resource configuration information; within each PMCH time slot, the gNB performs physical layer-related processing on the bit sequence mapped onto the PMCH according to the physical layer parameters of the PMCH; within each PMCH time slot, when transmitting the DMRS of the PMCH, the gNB generates the DMRS sequence of the PMCH according to the DMRS configuration information of the PMCH and maps the DMRS sequence to the specified time-frequency resources; within each PMCH time slot, when transmitting the PTRS of the PMCH, the gNB generates the PTRS sequence of the PMCH according to the PTRS configuration information of the PMCH and maps the PTRS sequence to the specified time-frequency resources.

[0150] For each PMCH, in order to transmit a TB from the MTCH through that PMCH, the gNB needs to configure at least one data MCS for that PMCH, determine the retransmission count for each TB on the PMCH, and determine the beam used for transmitting each TB. When a TB on the corresponding MCH of that PMCH originates from the MTCH, the gNB selects a data MCS from the data MCS configured for that PMCH to perform channel coding and modulation on that TB. For each PMCH, the gNB independently determines the retransmission count for each TB on that PMCH. However, for all PMCHs, the gNB uses the same set of beams to transmit each TB on these PMCHs.

[0151] For each PMCH, the gNB needs to determine the scheduling period for each PMCH and the mapping method between time slots and beams within the scheduling period. For each PMCH, the scheduling period is denoted by T, where T is in radio frames. The scheduling period of a PMCH is an integer multiple of the period P of its resource pool, i.e., T = P * K. The gNB dynamically schedules the PMCH in units of scheduling periods, allocating the resources contained in the PMCH within each scheduling period to the data of each MBS session carried on the corresponding MCH. The values ​​of P and K can differ for different PMCHs. The resource pools of different PMCHs do not overlap.

[0152] For each PMCH, the definition of the mapping method between time slots and beams within the PMCH scheduling period and the method of using the subscripts of the mapping method between time slots and beams within the PMCH scheduling period will be explained through a specific example.

[0153] For each PMCH, different scheduling strategies can be employed when scheduling the various MBS sessions carried on the corresponding MCH within each scheduling cycle. Accordingly, the PMCH configuration information also includes configuration information of the scheduling strategy adopted by the PMCH. This application will describe in detail the PMCH scheduling methods under different scheduling strategies through two embodiments. How the configuration information of the PMCH scheduling strategy is applied in PMCH scheduling will be described in detail in the corresponding embodiments.

[0154] Based on the above processing, gNB determines the configuration information for each PMCH. The configuration information for a PMCH includes:

[0155] (1) Configuration information of CFR in the SFN area

[0156] (2) List of MBS session configuration information for the MCH corresponding to the PMCH

[0157] (3) Configuration information of the PMCH resource pool: resource pool period P, resource pool starting radio frame offset SysFNOFFSET, starting time slot index TSOFFSET, PMCH time slot configuration information, PMCH time domain resource configuration information, physical layer parameters used by PMCH, PMCH DMRS configuration information, PMCH PTRS configuration information, at least one data MCS used by PMCH, number of repeated transmissions R per TB on PMCH, and N beams used when transmitting each TB.

[0158] (4) The scheduling period T of the PMCH and the subscript of the mapping method between time slots and beams within the scheduling period of the PMCH.

[0159] (5) Configuration information of the scheduling strategy adopted by PMCH:

[0160] PMCH can employ a time-division multiplexing scheduling strategy, or a scheduling strategy based on MRB group QoS requirements.

[0161] • When the PMCH adopts a scheduling strategy based on the QoS requirements of MRB groups, the configuration information of the scheduling strategy adopted by the PMCH includes: the number of MRB groups, the data MCS used by each MRB group, and the MTCH ID list corresponding to each MRB group: composed of the IDs of the MTCHs corresponding to each MRB contained in the MRB group.

[0162] 105. For each PMCH, gNB schedules the PMCH in each scheduling cycle and generates MBS scheduling information MAC CE for each scheduling cycle based on the scheduling results.

[0163] In this step, the scheduling process of gNB for each PMCH is illustrated through two specific examples.

[0164] 106. For each PMCH, within each scheduling period, the gNB generates a set of TBs based on the MBS scheduling information MACCE of that scheduling period, using the data of each MBS session carried on the MCH corresponding to the PMCH. It then determines a set of PMCH time slots within that scheduling period based on the index of the time slot-beam mapping method, and transmits the set of TBs through the set of PMCH time slots.

[0165] Specifically, for each PMCH, within each scheduling period, the gNB determines the number S of PMCH slots allocated to the PMCH within that scheduling period based on the MBS scheduling information MAC CE of that scheduling period, and determines the MCS to be used when transmitting the corresponding TB in each allocated PMCH slot. The gNB generates S TBs from the data of each MBS session carried on the MCH corresponding to the PMCH, and each TB corresponds to an allocated PMCH slot. The gNB uses the corresponding MCS when performing channel coding and modulation on the TB.

[0166] In each cell of the SFN area, the gNB determines N beams based on the N beams used when transmitting each TB in the PMCH configuration information. During the scheduling period, the gNB occupies the first S*R*N consecutive PMCH time slots to transmit the S TBs, where R is the number of times each TB is repeatedly transmitted in the PMCH configuration information. The gNB determines the beam used when transmitting the PMCH and the TB carried on the PMCH in each of the first S*R*N PMCH time slots of the scheduling period based on the index of the mapping method between time slots and beams in the PMCH configuration information. During each PMCH time slot, the gNB transmits the PMCH, the DMRS of the PMCH, and the PTRS of the PMCH.

[0167] The process of sending the PMCH, its DMRS, and its PTRS within each occupied PMCH time slot in each scheduling cycle is not the subject of this application and will not be described further.

[0168] In Embodiment 1 of this application, the gNB configures a Common Frequency Resource (CFR) for a Single Frequency Network (SFN) area, determining the Cyclic Prefix (CP) type, Subcarrier Spacing (SCS), and the location of a set of consecutive Common Resource Blocks (CRBs) occupied by the CFR. Based on a list of MBS sessions transmitted in SFN mode within the SFN area, the gNB configures several MBS Channels (MCHs) for the SFN area, determining the MBS sessions carried on each MCH. Each MCH is a dedicated transmission channel for MBS sessions within the SFN area. For each MCH, the gNB determines the configuration information for each MBS session carried on the MCH, generating a list of MBS session configuration information for the MCH. The gNB configures a Physical MBS Channel (Physical MBS Channel) for each MCH. MBSChannel (PMCH), PMCH is a physical channel dedicated to MBS sessions in the SFN area. Data of the MBS session carried on each MCH is mapped to a PMCH configured for that MCH. One MCH is selected from the configured MCHs to transmit transport blocks (TBs) from the logical channel MCCH. On the CFR of the SFN area, a periodically occurring resource pool is configured for each PMCH. Within each period, this resource pool consists of several PMCH time slots. When transmitting a PMCH within each PMCH time slot, all CRB resources on the CFR are used. Within each PMCH time slot, a continuous set of symbols is allocated to the PMCH, time-frequency resources are allocated to the PMCH demodulation reference signal DMRS, and time-frequency resources are allocated to the PMCH demodulation reference signal PTRS. For each PMCH, scheduling is performed within each scheduling period, and MBS scheduling information MAC CE is generated based on the scheduling results. When scheduling a PMCH, at least one data MCS configured for that PMCH is used. For each PMCH, the MBS scheduling information MAC generated within each scheduling period is used... The data of each MBS session carried on the CE and the MCH corresponding to the PMCH are used to determine the S TBs to be transmitted within the scheduling period. Each TB corresponds to a PMCH slot in the MBS scheduling information MAC CE for the corresponding scheduling period. When performing channel coding and modulation on the TB, the MCS configured for the corresponding PMCH slot is adopted. Within the scheduling period, the corresponding S*R*N PMCH slots are occupied to transmit S TBs. Within each occupied PMCH slot, the corresponding PMCH, PMCH DMRS and PMCH PTRS are transmitted.

[0169] In summary, Embodiment 1 of this application solves the problem of how to configure resources for an SFN area and how to schedule resources for transmitting data of various MBS sessions in that SFN area.

[0170] The following describes in detail the scheduling process for each PMCH in step 105 of the multicast service scheduling method proposed in Embodiment 1 of this application through two specific embodiments.

[0171] Specifically, such as Figure 2 As shown, Embodiment 2 of this application proposes a PMCH scheduling method based on a time-division multiplexing scheduling strategy. Specifically, the PMCH scheduling method based on a time-division multiplexing scheduling strategy proposed in Embodiment 2 of this application includes:

[0172] S21: For a PMCH, when the gNB configures a data MCS for the PMCH, the data MCS is used when scheduling the MTCH of each MBS session carried on the MCH corresponding to the PMCH; when the gNB configures multiple data MCSs for the PMCH, the gNB configures a data MCS for the MTCH of each MBS session carried on the MCH corresponding to the PMCH, and configures a data MCS for the MBS scheduling information MAC CE.

[0173] MBS scheduling information MAC CE is the scheduling information of PMCH within the current scheduling period and is very important. Therefore, preferably, the data MCS configured for MBS scheduling information MAC CE is the smallest data MCS among all data MCS configured for PMCH, so as to ensure that MBS scheduling information MAC CE is correctly received by UE.

[0174] Optionally, the same data MCS can be configured for all MTCHs of an MBS session.

[0175] Optionally, the same data MCS can be configured for each MBS session on the MCH corresponding to a PMCH.

[0176] Optionally, for each MTCH corresponding to each MRB of each MBS session, the data MCS adopted by the MTCH is determined based on the QoS requirements of each QoS flow mapped to the MRB, and the data MCS adopted by the MTCH must satisfy the QoS requirements of each QoS flow mapped to the MRB.

[0177] S22: For the current scheduling period of the PMCH, the gNB assigns PMCH slot numbers that can be used to send various MBS sessions within the current scheduling period in chronological order, starting from 0. Then, based on the data MCS configured for the MBS scheduling information MAC CE, the gNB reserves one PMCH slot or multiple consecutive PMCH slots for the MBS scheduling information MAC CE within the current scheduling period, starting from slot 0, for priority transmission of the MBS scheduling information MAC CE within the current scheduling period.

[0178] If there is an MCCH in the current scheduling period, the gNB will avoid using the PMCH slot occupied by the MCCH when assigning PMCH slot numbers that can be used to send various MBS sessions in the current scheduling period.

[0179] S23: gNB determines the starting time slot for scheduling each MBS session within the current scheduling cycle.

[0180] Specifically, when the last PMCH time slot occupied by the MBS scheduling information MAC CE is not fully occupied, the gNB uses that time slot as the starting time slot and starts scheduling each MBS session from that time slot; otherwise, the gNB uses the next PMCH time slot as the starting time slot and starts scheduling each MBS session from the next PMCH time slot.

[0181] S24: Starting from the initial time slot, the gNB schedules each MBS session sequentially within the current scheduling period until all MBS sessions have been scheduled or the resources in the PMCH resource pool have been allocated within the current scheduling period.

[0182] First, gNB uses one of the following methods to determine the scheduling order of each MBS session within the current scheduling period.

[0183] Method 1: If the data network has configured a priority for each MBS session, then the MBS sessions are scheduled sequentially from highest to lowest priority until all PMCH time slots in the current scheduling period are allocated or all MBS sessions are scheduled. For MBS sessions with the same priority, the PMCH time slots already allocated in the current scheduling period are excluded. If the remaining PMCH time slots in the current scheduling period are sufficient to transmit the data of these MBS sessions, then the MBS sessions are scheduled sequentially. If the remaining PMCH time slots in the current scheduling period are insufficient to transmit the data of these MBS sessions, then these MBS sessions can be randomly sorted or sorted according to the time order in which they were established, and then the MBS sessions are scheduled sequentially until all remaining PMCH time slots in the current scheduling period are allocated.

[0184] Method 2: If the data network configures a priority for each MBS session, then the MBS sessions are scheduled sequentially from highest to lowest priority until the PMCH time slots allocated in the current scheduling period are exhausted or all MBS sessions are scheduled. For MBS sessions with the same priority, the PMCH time slots already allocated in the current scheduling period are excluded. If the remaining PMCH time slots in the current scheduling period are sufficient to transmit the data of these MBS sessions, the MBS sessions are scheduled sequentially. If the remaining PMCH time slots in the current scheduling period are insufficient to transmit the data of these MBS sessions, the remaining PMCH time slots in the current scheduling period can be evenly distributed to these MBS sessions, or the remaining PMCH time slots in the current scheduling period can be used to evenly transmit the data of these MBS sessions. For each MBS session, preferably, the data on each MTCH of the MBS session is transmitted sequentially in ascending order of data MCS and then in ascending order of logical channel ID until the PMCH time slots allocated to the MBS session are used up or the amount of data allocated to the MBS session is used up, and then the scheduling of PMCH in the current scheduling period ends.

[0185] Method 3: If the data network does not assign a priority to each MBS session, then the MBS sessions will be randomly sorted or sorted according to the time order in which they were established, and the MBS sessions will be scheduled in sequence until the PMCH time slots in the current scheduling period are allocated or all MBS sessions are scheduled.

[0186] Method 4: If the data network does not assign priority to each MBS session, and if there are enough PMCH time slots available for transmitting data of each MBS session starting from the start time slot in the current scheduling period, then the MBS sessions are randomly sorted or sorted according to the establishment time order of each MBS session, and scheduled sequentially. Otherwise, the PMCH time slots starting from the start time slot in the current scheduling period are evenly distributed to each MBS session, or all PMCH time slots starting from the start time slot in the current scheduling period are used to evenly transmit the data of these MBS sessions. For each MBS session, preferably, the data on each MTCH of the MBS session is transmitted sequentially in ascending order of data MCS and then in ascending order of logical channel ID until the PMCH time slots allocated to the MBS session are used up or the amount of data allocated to the MBS session is used up, and then the scheduling of PMCH in the current scheduling period ends.

[0187] Then, gNB schedules each MBS session sequentially.

[0188] Specifically, when scheduling each MBS session, the gNB centrally allocates several consecutive PMCH time slots on each MTCH of the MBS session to carry the data of the MBS session.

[0189] When the last PMCH slot allocated to an MBS session is not filled with data from that MBS session, the gNB schedules the next MBS session starting from that slot; otherwise, the gNB schedules the next MBS session starting from the next PMCH slot.

[0190] When scheduling each MBS session, if the MTCHs of the MBS session use the same data MCS, then the MTCHs are scheduled in ascending order of logical channel ID. If the MTCHs of the MBS session do not use the same data MCS, then the MTCHs are scheduled in ascending order of data MCS and then in ascending order of logical channel ID. That is, the MTCHs are scheduled in ascending order of data MCS. For MTCHs with the same data MCS, the MTCHs are scheduled in ascending order of MTCH ID.

[0191] When scheduling an MTCH, if the data on that MTCH cannot fill a PMCH time slot, the next MTCH is scheduled starting from that PMCH time slot. When multiple MTCHs are scheduled simultaneously within a PMCH time slot, the data on these MTCHs is scheduled according to the smallest data MCS among these MTCHs. These MTCHs can be MTCHs of the same MBS session or MTCHs of different MBS sessions.

[0192] For each allocated PMCH time slot, the gNB determines the MCS used when transmitting the corresponding TB in the PMCH time slot: when only one MTCH is scheduled in the PMCH time slot, the MCS used when transmitting the corresponding TB in the PMCH time slot is the data MCS of the MTCH; otherwise, the MCS used when transmitting the corresponding TB in the PMCH time slot is the smallest data MCS among the data MCS of each MTCH scheduled in the PMCH time slot.

[0193] S25: gNB generates MBS scheduling information MACCE for the current scheduling period based on the scheduling results of the current scheduling period.

[0194] Based on the scheduling results of the scheduling process described in S24, the gNB generates MBS scheduling information MAC CE. The MBS scheduling information MAC CE provides an MBS session list, which includes:

[0195] (1) ID of each scheduled MBS session: TMGI

[0196] (2) Number of PMCH time slots occupied by each scheduled MBS session

[0197] (3) The MCS used when sending the corresponding TB in each PMCH time slot occupied by each scheduled MBS session.

[0198] Specifically, the MBS scheduling information MAC CE gives the ID of each scheduled MBS session. Starting from the first scheduled MBS session, the MBS scheduling information MAC CE gives the number of PMCH time slots occupied by each scheduled MBS session. The next scheduled MBS session can start transmitting from the last time slot of the previous scheduled MBS session at the earliest.

[0199] When calculating the PMCH time slots occupied by each scheduled MBS session, the PMCH time slots that transmit more than one MBS session at the same time are counted as the time slot of the first MBS session among the multiple MBS sessions.

[0200] For the first scheduled MBS session, the number of time slots occupied by the first scheduled MBS session is the total number of time slots used for transmitting MBS scheduling information MAC CE and the data of the first MBS session. Starting from the first time slot, the MBS scheduling information MAC CE is transmitted first, followed by the data of the first scheduled MBS session.

[0201] For each occupied PMCH time slot, the MBS scheduling information MAC CE also needs to provide the MCS used when sending the corresponding TB in that time slot.

[0202] In summary, Embodiment 2 of this application solves the technical problem of scheduling MBS sessions in the SFN manner by scheduling each PMCH through a time-division multiplexing scheduling strategy.

[0203] like Figure 3 As shown, Embodiment 3 of this application proposes a PMCH scheduling method based on radio bearer QoS requirements. Specifically, the PMCH scheduling method based on radio bearer QoS requirements proposed in Embodiment 3 of this application includes:

[0204] S31: For a PMCH, determine each MRB of each MBS session carried on the MCH corresponding to the PMCH, determine the QoS requirement of each MRB based on the QoS requirement of each QoS flow carried on each MRB, divide all MRBs into several groups, each group consisting of several MRBs with the same or similar QoS requirements; configure a data MCS for each group of MRBs, and use the data MCS configured for the group of MRBs when transmitting data on the MTCH corresponding to each MRB in the group of MRBs; configure a data MCS for the MBS scheduling information MACCE.

[0205] Preferably, the data MCS configured for each MRB group can meet the QoS requirements of the QoS streams mapped to each MRB in that MRB group.

[0206] S32: For the current scheduling period of the PMCH, the gNB assigns PMCH slot numbers that can be used to send various MBS sessions within the current scheduling period in chronological order, starting from slot 0. Then, based on the data MCS configured for the MBS scheduling information MAC CE, the gNB reserves one PMCH slot or multiple consecutive PMCH slots for the MBS scheduling information MAC CE within the current scheduling period, starting from slot 0, for priority transmission of the MBS scheduling information MAC CE within the current scheduling period.

[0207] If there is an MCCH in the current scheduling period, the gNB will avoid using the PMCH slot occupied by the MCCH when assigning PMCH slot numbers that can be used to send various MBS sessions in the current scheduling period.

[0208] S33: gNB determines the starting time slot for scheduling each MBS session within the current scheduling cycle.

[0209] The same as step S23, so I will not repeat it here.

[0210] S34: Starting from the initial time slot, gNB sequentially schedules each MRB group within the current scheduling period until the scheduling of all MRB groups is completed or the time slots in the PMCH resource pool are allocated within the current scheduling period.

[0211] Specifically, when scheduling MBS sessions carried on the MCH corresponding to the PMCH within the current scheduling period, one of the following methods can be used:

[0212] Method 1

[0213] Step 1: Before scheduling the MBS sessions carried on the MCH corresponding to the PMCH within the current scheduling period, the gNB needs to perform admission control on each MBS session according to the following method:

[0214] If there are sufficient resources to transmit data for each MBS session within the current scheduling period, then all MBS sessions can be scheduled within the current scheduling period; otherwise, starting with the MBS session with the highest priority, resources are allocated to each MBS session in descending order of priority within the current scheduling period until all resources within the current scheduling period have been allocated. For the last MBS session scheduled, resources are allocated first to the MRBs with high QoS requirements for that MBS session. Each scheduled MBS session is recorded. For the last scheduled MBS session, if only some of the MRBs in that MBS session are scheduled, each scheduled MRB for that MBS session is recorded.

[0215] Step 2: After admission control is performed on each MBS session, the gNB schedules each MRB group in ascending order of data MCS. When scheduling each MRB group, only the MTCH corresponding to the recorded MBS session or the MTCH corresponding to the recorded MRB is scheduled from the MTCH ID list of the MRB group.

[0216] Specifically, the gNB schedules each MRB group sequentially according to the ascending order of the data MCS. When scheduling each MRB group, it first determines the MTCH corresponding to each recorded MBS session and the MTCH corresponding to each recorded MRB in the MTCH ID list corresponding to the MRB group. For all determined MTCHs, these MTCHs are scheduled sequentially according to the ascending order of their MTCH IDs. When scheduling these MTCHs, the gNB allocates one or more PMCH time slots to each scheduled MTCH according to the data MCS configured for the MRB group, for transmitting data on that MTCH. When the last time slot allocated to a MTCH is not filled by data on that MTCH, the next MTCH is scheduled starting from that PMCH time slot.

[0217] When multiple MTCHs are scheduled simultaneously in a PMCH time slot, the data MCS used when scheduling these MTCHs in that PMCH time slot is the smallest data MCS among the data MCS used in the MRB group to which these MTCHs belong.

[0218] At the end of scheduling, the gNB determines each scheduled MRB group. For each scheduled MRB group, the gNB determines the total number of PMCH slots allocated to all scheduled MTCHs in the MTCH ID list corresponding to that MRB group. For each allocated PMCH slot, the gNB determines the MCS used when transmitting the corresponding TB in that PMCH slot: when only one MTCH is scheduled in that PMCH slot, the MCS used when transmitting the corresponding TB in that slot is the data MCS used by the MRB group corresponding to that MTCH; when multiple MTCHs are scheduled in that slot, the MCS used when transmitting the corresponding TB in that slot is the smallest data MCS among the data MCS used by the MRB groups corresponding to these scheduled MTCHs.

[0219] Method 2:

[0220] gNB schedules each MRB group sequentially in ascending order of data MCS until all MRB groups have been scheduled or the PMCH time slots within the current scheduling period have been allocated.

[0221] When scheduling each MRB group, MTCHs are scheduled sequentially from the MTCH ID list corresponding to that MRB group in ascending order of MTCH ID. When the PMCH slot allocated to an MTCH is not full, the next MTCH is scheduled starting from that PMCH slot. If a PMCH slot transmits data from multiple MTCHs simultaneously, the data MCS used when transmitting data from these MTCHs is the smallest data MCS among the data MCSs used by the MRB groups corresponding to these MTCHs.

[0222] At the end of scheduling, the gNB determines the ID of each scheduled MRB group. For each scheduled MRB group, the gNB determines the total number of PMCH slots allocated to all scheduled MTCHs in the MTCH ID list corresponding to that MRB group. For each allocated PMCH slot, the gNB determines the MCS used when transmitting the corresponding TB in that PMCH slot: when only one MTCH is scheduled in that PMCH slot, the MCS used when transmitting the corresponding TB in that slot is the data MCS used by the MRB group corresponding to that MTCH; when multiple MTCHs are scheduled in that slot, the MCS used when transmitting the corresponding TB in that slot is the smallest data MCS among the data MCS used by the MRB groups corresponding to these scheduled MTCHs.

[0223] Method 3:

[0224] The gNB schedules each MRB group in ascending order of data MCS. When scheduling an MRB group, the PMCH time slots already allocated in the current scheduling period are excluded. If the remaining PMCH time slots in the current scheduling period are sufficient to transmit the data on each MTCH in the MTCH ID list corresponding to the MRB group, the MTCHs are scheduled in ascending order of MTCH ID. If the remaining PMCH time slots in the current scheduling period are insufficient to transmit the data on each MTCH in the MTCH ID list corresponding to the MRB group, the remaining PMCH time slots are used to evenly transmit the data on each MTCH in the MTCH ID list corresponding to the MRB group.

[0225] When a time slot allocated to an MTCH is not fully occupied by data on that MTCH, the next MTCH is scheduled starting from that PMCH time slot. When multiple MTCHs are scheduled simultaneously in a PMCH time slot, the data MCS used when scheduling these MTCHs in that PMCH time slot is the smallest data MCS among the data MCS used by the MRB groups corresponding to these MTCHs.

[0226] At the end of scheduling, the gNB determines the ID of each scheduled MRB group. For each scheduled MRB group, the gNB determines the total number of PMCH slots allocated to all scheduled MTCHs in the MTCH ID list corresponding to that MRB group. For each allocated PMCH slot, the gNB determines the MCS used when transmitting the corresponding TB in that PMCH slot: when only one MTCH is scheduled in that PMCH slot, the MCS used when transmitting the corresponding TB in that slot is the data MCS used by the MRB group corresponding to that MTCH; when multiple MTCHs are scheduled in that slot, the MCS used when transmitting the corresponding TB in that slot is the smallest data MCS among the data MCS used by the MRB groups corresponding to these scheduled MTCHs.

[0227] S35: gNB generates MBS scheduling information MACCE for the current scheduling period based on the scheduling results of the current scheduling period.

[0228] Specifically, the gNB provides an MRB group list based on the MBS scheduling information MAC CE generated from the scheduling results. This list provides:

[0229] (1) ID of each scheduled MRB group:

[0230] (2) The number of PMCH slots allocated by gNB to each scheduled MRB group, i.e., the number of PMCH slots allocated by gNB to each MTCH in the MTCH ID list corresponding to the MRB group.

[0231] (3) The MCS used when transmitting the corresponding TB in each PMCH time slot allocated to each scheduled MRB group.

[0232] Specifically, at the end of the scheduling process, the gNB generates a MBS scheduling information MAC CE based on the scheduling results. This MBS scheduling information MAC CE provides the ID of each scheduled MRB group, starting from the first scheduled MRB group, and also indicates the number of PMCH time slots occupied by each scheduled MRB group. The next scheduled MRB group can begin transmission no earlier than the last time slot occupied by the previous scheduled MRB group.

[0233] When calculating the PMCH time slots occupied by each MRB group, for PMCH time slots that transmit more than one MRB group simultaneously, they are counted as the time slot of the first MRB group among the multiple MRB groups.

[0234] For the first scheduled MRB group, the number of time slots occupied by this MRB group is the total number of time slots used for transmitting the MBS scheduling information MACCE and the data of the first scheduled MRB group. Starting from the first time slot, the MBS scheduling information MACCE is transmitted first, followed by the data of the first scheduled MRB group.

[0235] For each PMCH slot allocated to each scheduled MRB group, the MBS scheduling information MAC CE gives the MCS used when transmitting the corresponding TB in that PMCH slot.

[0236] In summary, the PMCH scheduling method based on unlimited bearer QoS requirements proposed in Embodiment 3 of this application solves the technical problem of scheduling MBS sessions in SFN mode.

[0237] The following describes in detail the definition and usage of the mapping method between time slots and beams within the PMCH scheduling period in step 104 of embodiment one of this application, using a method for determining the mapping method between time slots and beams within the PMCH scheduling period proposed in embodiment four of this application. Specifically, the method for determining the mapping method between time slots and beams within the PMCH scheduling period proposed in embodiment four of this application includes:

[0238] For a PMCH, the mapping method between PMCH time slots and beams in each scheduling cycle is defined as follows:

[0239] First, gNB assigns PMCH slot numbers, starting from 0, to the PMCH slots that can be used to send various MBS sessions within the current scheduling period, in chronological order.

[0240] Each PMCH contains Duration*(T / P) PMCH slots within each scheduling period, where Duration is the number of PMCH slots included in the PMCH resource pool within each period. All PMCH slots can be used to send various MBS sessions within each scheduling period, except for the slots occupied by the MCCH.

[0241] Then, gNB generates S TBs based on the MBS scheduling information MAC CE of the current scheduling period and the data on each MTCH of each MBS session on the MCH corresponding to the PMCH, and determines the MCS used by each TB, where S is the total number of PMCH slots allocated to the PMCH in the MBS scheduling information MAC CE of the current scheduling period.

[0242] According to the PMCH configuration information, the gNB transmits the S TBs through the PMCH based on the number of retransmissions R for each TB and the N beams used to transmit each TB in the current scheduling period, occupying the first S*R*N time slots.

[0243] When the gNB occupies the first S*R*N time slots in the current scheduling period and transmits the S TBs through the PMCH, the beam used to transmit the PMCH and the TB carried on the PMCH in each occupied PMCH time slot are determined according to one of the following PMCH time slot to beam mapping methods:

[0244] (1) Mapping method 0:

[0245] The S*R*N time slots can be divided into S groups, each containing N*R consecutive time slots, and the S TBs can be transmitted through the S groups. Further, the N*R time slots within each group can be divided into R subgroups, each containing N consecutive time slots. The corresponding TB is transmitted R times through the R subgroups, and within each subgroup, the corresponding TB is transmitted once in different beam directions within N time slots.

[0246] (2) Mapping method 1:

[0247] The S*R*N time slots can be divided into S groups, each containing N*R time slots, and the S data points (TBs) can be transmitted through the S groups. Further, the N*R time slots within each group are divided into N subgroups, each containing R consecutive time slots, and the corresponding TBs are transmitted through the N subgroups in N beam directions. Within each subgroup, the corresponding TB is transmitted R times in the same beam direction using the R time slots.

[0248] (3) Mapping method 2:

[0249] The S*R*N time slots can be divided into R groups, each containing N*S time slots. The S data points (TBs) are then repeatedly transmitted R times through the R groups. Further, the N*S time slots within each group are divided into S subgroups, each containing N consecutive time slots. The S TBs are transmitted through the S subgroups respectively. Within each subgroup, the same TB is transmitted once in different beam directions through N time slots.

[0250] (4) Mapping method 3:

[0251] The S*R*N time slots can be divided into R groups, each containing N*S time slots. The S data points (TBs) are then repeatedly transmitted R times through the R groups. Further, the N*S time slots within each group are divided into N subgroups, each containing S consecutive time slots. The S TBs are then transmitted through the N subgroups in N beam directions. Within each subgroup, S TBs are transmitted in the same beam direction through S time slots.

[0252] Based on the above four mapping methods for time slots and beams within a scheduling period, the mapping method for PMCH time slots and beams within a scheduling period can be configured using one of the following methods:

[0253] Method 1: In the 3GPP NR protocol, the mapping method between PMCH time slots and beams within the PMCH scheduling cycle is fixed as: mapping method 0 / 1 / 2 / 3.

[0254] Method 2: Configure the mapping method between PMCH time slots and beams within the PMCH scheduling period using a pre-configuration method and a configuration method based on Radio Resource Control (RRC) signaling.

[0255] Specifically, the mapping method between PMCH time slots and beams within the PMCH scheduling period can be pre-configured as mapping method 0 / 1 / 2 / 3 in the 3GPP NR protocol. If the mapping method between PMCH time slots and beams is not provided in the PMCH configuration information, the pre-configured mapping method is used by default; otherwise, the mapping method provided in the PMCH configuration information is used. When configuring the mapping method between PMCH time slots and beams within the PMCH scheduling period using the pre-configured method and the configuration method based on RRC signaling, optionally, the PMCH resource pool configuration information includes the parameter: PMCH time slot and beam mapping method, which gives the index of the mapping method used.

[0256] This application provides a gNB (gender-based NodeB) for implementing a multicast / broadcast service scheduling method in an NR system as provided in Embodiment 1 of this application. Specifically, the gNB includes the following functions:

[0257] The gNB configures a Common Frequency Resource (CFR) for an SFN area and determines the configuration information of the CFR. The CFR of the SFN area consists of several consecutive Common Resource Blocks (CRBs) in the entire bandwidth of the carrier frequency used by the SFN area. Each cell in the SFN area uses the CFR configured for the SFN area to send various MBS sessions of the SFN area.

[0258] The gNB configures several MBS channels (MCHs) for the SFN area based on a list of MBS sessions transmitted in SFN mode within the SFN area, and determines the MBS sessions carried on each MCH. Each MCH is a dedicated transmission channel for MBS sessions within the SFN area. For each MCH, the gNB determines the configuration information for each MBS session carried on the MCH and generates a list of MBS session configuration information for that MCH. The gNB configures a Physical MBS Channel (PMCH) for each MCH. Each PMCH is a dedicated physical channel for MBS sessions within the SFN area, and the data of the MBS sessions carried on each MCH is mapped to the PMCH configured for that MCH.

[0259] The gNB selects one MCH from the configured MCHs for transmitting a transport block (TB) from the MBS Control Channel (MCCH) of the SFN area.

[0260] The gNB configures a periodically occurring resource pool for each PMCH on the CFR of the SFN area, determines the scheduling period of each PMCH and the mapping method between time slots and beams within the scheduling period, and determines the configuration information of each PMCH.

[0261] For each PMCH, the gNB schedules the PMCH in each scheduling cycle of the PMCH and generates MBS scheduling information MAC CE for each scheduling cycle based on the scheduling results;

[0262] For each PMCH, within each scheduling period, the gNB generates a set of TBs based on the MBS scheduling information MACCE of that scheduling period, using the data of each MBS session carried on the MCH corresponding to the PMCH. It then determines a set of PMCH time slots within that scheduling period based on the index of the time slot-beam mapping method, and transmits the set of TBs through the set of PMCH time slots.

[0263] Other embodiments of this disclosure will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this disclosure are indicated by the following claims.

[0264] It should be understood that this disclosure is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this disclosure is limited only by the appended claims.

Claims

1. A scheduling method for multicast services in an NR system, characterized in that, Applied to a next-generation wireless access network (gNB), the method includes: The gNB configures a Common Frequency Resource (CFR) for an SFN area and determines the configuration information of the CFR. The CFR of the SFN area consists of several consecutive Common Resource Blocks (CRBs) in the entire bandwidth of the carrier frequency used by the SFN area. Each cell in the SFN area uses the CFR configured for the SFN area to send various MBS sessions of the SFN area. Based on a list of MBS sessions transmitted in SFN mode within the SFN area, the gNB configures several MBS channels (MCHs) for the SFN area, determines the MBS sessions carried on each MCH, and the MCH is a dedicated transmission channel for MBS sessions in the SFN area. For each MCH, the gNB determines the configuration information of each MBS session carried on the MCH and generates a list of MBS session configuration information for the MCH. The gNB configures a physical MBS channel (PMCH) for each MCH, and the PMCH is a dedicated physical channel for MBS sessions in the SFN area. The data of the MBS sessions carried on each MCH is mapped to the PMCH configured for the MCH. The gNB selects one MCH from the configured MCHs for transmitting a transport block (TB) from the MBS Control Channel (MCCH) of the SFN area. The gNB configures a periodically occurring resource pool for each PMCH on the CFR in the SFN area, determines the scheduling period of each PMCH and the mapping method between time slots and beams within the scheduling period, and determines the configuration information of each PMCH. For each PMCH, gNB schedules the PMCH in each scheduling cycle and generates MBS scheduling information MAC CE for each scheduling cycle based on the scheduling results; For each PMCH, within each scheduling period, the gNB generates a set of TBs based on the MBS scheduling information MAC CE of that scheduling period, using the data of each MBS session carried on the MCH corresponding to the PMCH. It then determines a set of PMCH time slots within that scheduling period based on the index of the time slot-beam mapping method, and transmits the set of TBs through the set of PMCH time slots.

2. The method according to claim 1, characterized in that, For each PMCH, the gNB schedules the PMCH within each scheduling period of that PMCH, and generates MBS scheduling information MAC CE for each scheduling period based on the scheduling results, including: For a PMCH, when the gNB configures a data MCS for the PMCH, the data MCS is used when scheduling the MTCH of each MBS session carried on the MCH corresponding to the PMCH; when the gNB configures multiple data MCSs for the PMCH, the gNB configures a data MCS for the MTCH of each MBS session carried on the MCH corresponding to the PMCH, and configures a data MCS for the MBS scheduling information MAC CE. For the current scheduling period of the PMCH, the gNB assigns PMCH slot numbers that can be used to send various MBS sessions within the current scheduling period in chronological order, starting from 0. Then, based on the data MCS configured for the MBS scheduling information MAC CE, the gNB reserves one PMCH slot or multiple consecutive PMCH slots for the MBS scheduling information MAC CE within the current scheduling period, starting from slot 0, for priority transmission of the MBS scheduling information MAC CE within the current scheduling period. The gNB determines the starting time slot for scheduling each MBS session within the current scheduling cycle. The gNB schedules each MBS session sequentially within the current scheduling period, starting from the initial time slot, until all MBS sessions have been scheduled or the resources in the PMCH resource pool have been allocated within the current scheduling period.

3. The method according to claim 2, characterized in that, The gNB schedules each MBS session sequentially within the current scheduling period, starting from the initial time slot, until all MBS sessions have been scheduled or the resources in the PMCH resource pool have been allocated within the current scheduling period, including: gNB uses one of the following methods to determine the scheduling order of each MBS session within the current scheduling period: Method 1: If the data network has configured a priority for each MBS session, then the MBS sessions are scheduled sequentially from highest to lowest priority until all PMCH time slots in the current scheduling period are allocated or all MBS sessions are scheduled. For MBS sessions with the same priority, the PMCH time slots already allocated in the current scheduling period are excluded. If the remaining PMCH time slots in the current scheduling period are sufficient to transmit the data of these MBS sessions, then the MBS sessions are scheduled sequentially. If the remaining PMCH time slots in the current scheduling period are insufficient to transmit the data of these MBS sessions, then these MBS sessions can be randomly sorted or sorted according to the time order in which they were established, and then the MBS sessions are scheduled sequentially until all remaining PMCH time slots in the current scheduling period are allocated. Method 2: If the data network configures a priority for each MBS session, then the MBS sessions are scheduled sequentially from highest to lowest priority until the PMCH time slots in the current scheduling period are fully allocated or all MBS sessions are scheduled. For MBS sessions with the same priority, the PMCH time slots already allocated in the current scheduling period are excluded. If the remaining PMCH time slots in the current scheduling period are sufficient to transmit the data of these MBS sessions, the MBS sessions are scheduled sequentially. If the remaining PMCH time slots in the current scheduling period are insufficient to transmit the data of these MBS sessions, the remaining PMCH time slots in the current scheduling period can be evenly distributed to these MBS sessions, or the remaining PMCH time slots in the current scheduling period can be used to evenly transmit the data of these MBS sessions. For each MBS session, the data on each MTCH of the MBS session is transmitted sequentially in ascending order of data MCS and then in ascending order of logical channel ID until the PMCH time slots allocated to the MBS session are used up or the amount of data allocated to the MBS session is used up. Then, the scheduling of PMCH in the current scheduling period ends. Method 3: If the data network does not configure priority for each MBS session, then the MBS sessions are randomly sorted or sorted according to the establishment time of each MBS session, and the MBS sessions are scheduled in sequence until the PMCH time slots in the current scheduling period are allocated or all MBS sessions are scheduled. Method 4: If the data network does not assign priority to each MBS session, and if there are enough PMCH time slots available for transmitting data of each MBS session starting from the start time slot in the current scheduling period, then the MBS sessions are randomly sorted or sorted according to the establishment time order of each MBS session, and scheduled sequentially. Otherwise, the PMCH time slots starting from the start time slot in the current scheduling period are evenly distributed to each MBS session, or all PMCH time slots starting from the start time slot in the current scheduling period are used to evenly transmit the data of these MBS sessions: For each MBS session, the data on each MTCH of the MBS session is transmitted sequentially in ascending order of data MCS and then in ascending order of logical channel ID until the PMCH time slots allocated to the MBS session are used up or the amount of data allocated to the MBS session is used up, and then the scheduling of PMCH in the current scheduling period ends. Then, gNB schedules each MBS session sequentially.

4. The method according to claim 3, characterized in that, The gNB schedules each MBS session sequentially, including: When scheduling each MBS session, the gNB centrally allocates several consecutive PMCH time slots on each MTCH of the MBS session to carry the data of the MBS session. When the last PMCH slot allocated to an MBS session is not filled with data from that MBS session, the gNB schedules the next MBS session starting from that slot; otherwise, the gNB schedules the next MBS session starting from the next PMCH slot. When scheduling each MBS session, if the MTCH of the MBS session uses the same data MCS, the MTCHs are scheduled in ascending order of logical channel ID; if the MTCHs of the MBS session do not use the same data MCS, the MTCHs are scheduled in ascending order of data MCS first and then in ascending order of logical channel ID. When scheduling an MTCH, if the data on the MTCH cannot fill a PMCH time slot, the next MTCH is scheduled starting from the PMCH time slot; when multiple MTCHs are scheduled simultaneously in a PMCH time slot, the data on these MTCHs is scheduled according to the smallest data MCS among the data MCS of these MTCHs; these MTCHs can be MTCHs of the same MBS session or MTCHs of different MBS sessions. For each allocated PMCH time slot, the gNB determines the MCS used when transmitting the corresponding TB in the PMCH time slot: when only one MTCH is scheduled in the PMCH time slot, the MCS used when transmitting the corresponding TB in the PMCH time slot is the data MCS of the MTCH; otherwise, the MCS used when transmitting the corresponding TB in the PMCH time slot is the smallest data MCS among the data MCS of each MTCH scheduled in the PMCH time slot.

5. The method according to claim 2, characterized in that, The gNB generates MBS scheduling information MAC CE for the current scheduling period based on the scheduling result of the current scheduling period, including: The MBS scheduling information MAC CE provides a list of MBS sessions, which provides: (1) ID of each scheduled MBS session: TMGI; (2) The number of PMCH time slots occupied by each scheduled MBS session; (3) The MCS used when sending the corresponding TB in each PMCH time slot occupied by each scheduled MBS session.

6. The method according to claim 1, characterized in that, For each PMCH, the gNB schedules the PMCH within each scheduling period of that PMCH, and generates MBS scheduling information MAC CE for each scheduling period based on the scheduling results, including: For a PMCH, the gNB determines each MRB of each MBS session carried on the MCH corresponding to the PMCH, determines the QoS requirements of each MRB based on the QoS requirements of each QoS flow carried on each MRB, divides all MRBs into several groups, each group consisting of several MRBs with the same or similar QoS requirements, configures a data MCS for each group of MRBs, and uses the data MCS configured for the group of MRBs when transmitting data on the MTCH corresponding to each MRB in the group of MRBs; configures a data MCS for the MBS scheduling information MACCE. For the current scheduling period of the PMCH, the gNB assigns PMCH slot numbers that can be used to send various MBS sessions within the current scheduling period in chronological order, starting from 0. Then, based on the data MCS configured for the MBS scheduling information MAC CE, the gNB reserves one PMCH slot or multiple consecutive PMCH slots for the MBS scheduling information MAC CE within the current scheduling period, starting from slot 0, for priority transmission of the MBS scheduling information MAC CE within the current scheduling period. The gNB determines the starting time slot for scheduling each MBS session within the current scheduling cycle. The gNB starts from the initial time slot and schedules each MRB group sequentially within the current scheduling period until the scheduling of all MRB groups is completed or the time slots in the PMCH resource pool are allocated within the current scheduling period. The gNB generates MBS scheduling information MAC CE for the current scheduling period based on the scheduling result of the current scheduling period.

7. The method according to claim 6, characterized in that, The gNB, starting from the initial time slot, sequentially schedules each MRB group within the current scheduling period until the scheduling of all MRB groups is completed or the time slot allocation within the PMCH resource pool is completed within the current scheduling period, including: Before scheduling the MBS sessions carried on the MCH corresponding to the PMCH in the current scheduling cycle, the gNB needs to perform admission control on each MBS session according to the following method: If there are sufficient resources to transmit data for each MBS session within the current scheduling period, then all MBS sessions can be scheduled within the current scheduling period; otherwise, within the current scheduling period, resources are allocated to each MBS session in descending order of priority, starting with the MBS session with the highest priority, until all resources within the current scheduling period are allocated; for the last MBS session scheduled, resources are allocated to the MRBs with high QoS requirements of that MBS session first, and each scheduled MBS session is recorded; for the last MBS session scheduled, if only some of the MRBs in all the MRBs of that MBS session are scheduled, each scheduled MRB of that MBS session is recorded. After admission control is applied to each MBS session, the gNB schedules each MRB group in ascending order of data MCS. When scheduling each MRB group, only the MTCH corresponding to the recorded MBS session or the MTCH corresponding to the recorded MRB is scheduled from the MTCH ID list of the MRB group.

8. The method according to claim 7, characterized in that, The step of scheduling each MRB group by scheduling only the MTCH corresponding to the recorded MBS session or the MTCH corresponding to the recorded MRB in the MTCH ID list for that MRB group includes: The gNB schedules each MRB group in ascending order of data MCS. When scheduling each MRB group, it first determines the MTCH corresponding to each recorded MBS session and the MTCH corresponding to each recorded MRB in the MTCH ID list corresponding to the MRB group. For all determined MTCHs, these MTCHs are scheduled in ascending order of MTCH ID. When scheduling these MTCHs, the gNB allocates one or more PMCH time slots to each scheduled MTCH according to the data MCS configured for the MRB group for transmitting data on the MTCH. When the last time slot allocated to the MTCH is not filled by the data on the MTCH, the next MTCH is scheduled starting from the PMCH time slot. When multiple MTCHs are scheduled simultaneously in a PMCH time slot, the data MCS used when scheduling these MTCHs in that PMCH time slot is the smallest data MCS among the data MCS used in the MRB group to which these MTCHs belong. At the end of scheduling, the gNB determines each scheduled MRB group. For each scheduled MRB group, the gNB determines the total number of PMCH slots allocated to all scheduled MTCHs in the MTCH ID list corresponding to that MRB group. For each allocated PMCH slot, the gNB determines the MCS used when transmitting the corresponding TB in that PMCH slot: when only one MTCH is scheduled in that PMCH slot, the MCS used when transmitting the corresponding TB in that slot is the data MCS used by the MRB group corresponding to that MTCH; when multiple MTCHs are scheduled in that slot, the MCS used when transmitting the corresponding TB in that slot is the smallest data MCS among the data MCS used by the MRB groups corresponding to these scheduled MTCHs.

9. The method according to claim 6, characterized in that, The gNB, starting from the initial time slot, sequentially schedules each MRB group within the current scheduling period until the scheduling of all MRB groups is completed or the time slot allocation within the PMCH resource pool is completed within the current scheduling period, including: gNB schedules each MRB group in ascending order of data MCS until all MRB groups have been scheduled or the PMCH time slots in the current scheduling period have been allocated. When scheduling each MRB group, each MTCH in the MTCH ID list corresponding to the MRB group is scheduled in ascending order of MTCH ID; when the PMCH slot allocated to an MTCH is not full, the next MTCH is scheduled starting from that PMCH slot; if a PMCH slot transmits data on multiple MTCHs at the same time, the data MCS used when transmitting data on these MTCHs is the smallest data MCS among the data MCS used by the MRB groups corresponding to these MTCHs; At the end of scheduling, the gNB determines the ID of each scheduled MRB group. For each scheduled MRB group, the gNB determines the total number of PMCH slots allocated to all scheduled MTCHs in the MTCH ID list corresponding to that MRB group. For each allocated PMCH slot, the gNB determines the MCS used when transmitting the corresponding TB in that PMCH slot: when only one MTCH is scheduled in that PMCH slot, the MCS used when transmitting the corresponding TB in that slot is the data MCS used by the MRB group corresponding to that MTCH; when multiple MTCHs are scheduled in that slot, the MCS used when transmitting the corresponding TB in that slot is the smallest data MCS among the data MCS used by the MRB groups corresponding to these scheduled MTCHs.

10. The method according to claim 6, characterized in that, The gNB, starting from the initial time slot, sequentially schedules each MRB group within the current scheduling period until the scheduling of all MRB groups is completed or the time slot allocation within the PMCH resource pool is completed within the current scheduling period, including: The gNB schedules each MRB group in ascending order of data MCS. When scheduling an MRB group, the PMCH time slots already allocated in the current scheduling period are excluded. If the remaining PMCH time slots in the current scheduling period are sufficient to transmit the data on each MTCH in the MTCH ID list corresponding to the MRB group, the MTCHs are scheduled in ascending order of MTCH ID. If the remaining PMCH time slots in the current scheduling period are insufficient to transmit the data on each MTCH in the MTCH ID list corresponding to the MRB group, the remaining PMCH time slots are used to evenly transmit the data on each MTCH in the MTCH ID list corresponding to the MRB group. When the time slot allocated to an MTCH is not filled by the data on that MTCH, the next MTCH is scheduled starting from that PMCH time slot; when multiple MTCHs are scheduled in a PMCH time slot at the same time, the data MCS used when scheduling these MTCHs in that PMCH time slot is the smallest data MCS among the data MCS used by the MRB groups corresponding to these MTCHs. At the end of scheduling, the gNB determines the ID of each scheduled MRB group. For each scheduled MRB group, the gNB determines the total number of PMCH slots allocated to all scheduled MTCHs in the MTCH ID list corresponding to that MRB group. For each allocated PMCH slot, the gNB determines the MCS used when transmitting the corresponding TB in that PMCH slot: when only one MTCH is scheduled in that PMCH slot, the MCS used when transmitting the corresponding TB in that slot is the data MCS used by the MRB group corresponding to that MTCH; when multiple MTCHs are scheduled in that slot, the MCS used when transmitting the corresponding TB in that slot is the smallest data MCS among the data MCS used by the MRB groups corresponding to these scheduled MTCHs.

11. The method according to claim 6, characterized in that, The gNB generates MBS scheduling information MAC CE for the current scheduling period based on the scheduling result of the current scheduling period, including: The MBS scheduling information MAC CE provides an MRB group list, which provides: (1) ID of each scheduled MRB group: (2) The number of PMCH slots allocated by gNB to each scheduled MRB group, that is: the number of PMCH slots allocated by gNB to each MTCH in the MTCHID list corresponding to the MRB group. (3) The MCS used when transmitting the corresponding TB in each PMCH time slot allocated to each scheduled MRB group.

12. The method according to claim 1, characterized in that, For each PMCH, the configuration information of the PMCH includes: (1) Configuration information of CFR in the SFN area; (2) The list of MBS session configuration information for the MCH corresponding to the PMCH; (3) Configuration information of the PMCH resource pool: the period P of the resource pool, the initial radio frame offset SysFNOFFSET of the resource pool in each period, the initial time slot index TSOFFSET, the PMCH time slot configuration information, the PMCH time domain resource configuration information, the physical layer parameters used by the PMCH, the PMCH DMRS configuration information, the PMCH PTRS configuration information, the at least one data MCS used by the PMCH, the number of repeated transmissions R for each TB on the PMCH, and the N beams used when transmitting each TB. (4) The scheduling period T of the PMCH and the subscript of the mapping method between time slots and beams within the scheduling period of the PMCH; (5) Configuration information of the scheduling strategy adopted by PMCH.

13. The method according to claim 12, characterized in that, The configuration information for each MBS session in the MBS session configuration information list corresponding to the PMCH includes: (1) MBS session ID: TMGI; (2) Service Data Adaptation Protocol (SDAP) configuration information for MBS session: gNB configures an SDAP entity for the MBS session based on this information, which is used to map the QoS stream of the MBS session to one or more MBS Radio Bearers (MRBs). (3) Packet Data Convergence Protocol (PDCP) configuration information for each MRB of the MBS session: gNB configures a PDCP entity for each MRB of the MBS session based on this information; (4) Radio Link Control (RLC) configuration information for each MRB of the MBS session: The gNB configures an Unacknowledged Mode (UM) RLC entity for each MRB of the MBS session based on this information; (5) MBS Traffic Channel (MTCH) configuration information of MBS session: gNB configures an MTCH for each MRB of the MBS session and determines the ID of each MTCH. The MTCH configuration information of the MBS session consists of the IDs of each MTCH of the MBS session.

14. The method according to claim 12, characterized in that, The mapping method between time slots and beams within the scheduling period of the PMCH includes: First, gNB assigns PMCH slot numbers, starting from 0 and in chronological order, to the PMCH slots that can be used to send various MBS sessions within the current scheduling period. Then, gNB generates S TBs based on the MBS scheduling information MAC CE of the current scheduling period and the data on each MTCH of each MBS session on the MCH corresponding to the PMCH, and determines the MCS used by each TB. S is the total number of PMCH slots allocated to the PMCH in the MBS scheduling information MAC CE of the current scheduling period. According to the repetition count R of each TB in the configuration information of the PMCH and the N beams used when transmitting each TB in the configuration information of the PMCH, the gNB occupies the first S*R*N time slots in the current scheduling period to transmit the S TBs through the PMCH. When the gNB occupies the first S*R*N time slots in the current scheduling period and transmits the S TBs through the PMCH, the beam used to transmit the PMCH and the TB carried on the PMCH in each occupied PMCH time slot are determined according to one of the following PMCH time slot to beam mapping methods: (1) Mapping method 0: The S*R*N time slots can be divided into S groups, each group containing N*R consecutive time slots, and the S TBs can be transmitted through the S groups; further, the N*R time slots in each group can be divided into R subgroups, each subgroup containing N consecutive time slots, and the corresponding TBs can be repeatedly transmitted R times through the R subgroups, and the corresponding TBs can be transmitted once in different beam directions within the N time slots in each subgroup; (2) Mapping method 1: The S*R*N time slots can be divided into S groups, each containing N*R time slots, and the S TBs can be transmitted through the S groups; further, the N*R time slots in each group can be divided into N subgroups, each subgroup containing R consecutive time slots, and the corresponding TBs can be transmitted in N beam directions through the N subgroups respectively; within each subgroup, the corresponding TBs can be transmitted R times in the same beam direction through the R time slots; (3) Mapping method 2: The S*R*N time slots can be divided into R groups, each group containing N*S time slots, and the S TBs can be repeatedly transmitted R times through the R groups; further, the N*S time slots in each group can be divided into S subgroups, each subgroup containing N consecutive time slots, and the S TBs can be transmitted through the S subgroups respectively; within each subgroup, the same TB can be transmitted once in different beam directions through N time slots; (4) Mapping method 3: The S*R*N time slots can be divided into R groups, each group containing N*S time slots, and the S TBs can be repeatedly transmitted R times through the R groups; further, the N*S time slots in each group can be divided into N subgroups, each subgroup containing S consecutive time slots, and the S TBs can be transmitted in N beam directions through the N subgroups respectively; within each subgroup, S TBs can be transmitted in the same beam direction through the S time slots respectively; Based on the different mapping methods of time slots and beams within the above scheduling periods, the mapping method of PMCH time slots and beams within the scheduling period can be configured using one of the following methods: Method 1: In the 3GPP NR protocol, the mapping method between PMCH time slots and beams within the PMCH scheduling cycle is fixed as: mapping method 0 / 1 / 2 / 3; Method 2: Configure the mapping method between PMCH time slots and beams within the PMCH scheduling period using a pre-configuration method and a configuration method based on Radio Resource Control (RRC) signaling.

15. An apparatus for implementing a scheduling method for multicast services in an NR system, the apparatus being a gNB, the gNB comprising the following functions: The gNB configures a Common Frequency Resource (CFR) for an SFN area and determines the configuration information of the CFR. The CFR of the SFN area consists of several consecutive Common Resource Blocks (CRBs) in the entire bandwidth of the carrier frequency used by the SFN area. Each cell in the SFN area uses the CFR configured for the SFN area to send various MBS sessions of the SFN area. The gNB configures several MBS channels (MCHs) for the SFN area based on a list of MBS sessions transmitted in SFN mode within the SFN area, and determines the MBS sessions carried on each MCH. Each MCH is a dedicated transmission channel for MBS sessions within the SFN area. For each MCH, the gNB determines the configuration information for each MBS session carried on the MCH and generates a list of MBS session configuration information for that MCH. The gNB configures a physical MBS channel (PMCH) for each MCH. Each PMCH is a dedicated physical channel for MBS sessions within the SFN area, and the data of the MBS sessions carried on each MCH is mapped to the PMCH configured for that MCH. The gNB selects one MCH from the configured MCHs for transmitting a transport block (TB) from the MBS Control Channel (MCCH) of the SFN area. The gNB configures a periodically occurring resource pool for each PMCH on the CFR of the SFN area, determines the scheduling period of each PMCH and the mapping method between time slots and beams within the scheduling period, and determines the configuration information of each PMCH. For each PMCH, the gNB schedules the PMCH in each scheduling cycle of the PMCH and generates MBS scheduling information MAC CE for each scheduling cycle based on the scheduling results; For each PMCH, within each scheduling period, the gNB generates a set of TBs based on the MBS scheduling information MAC CE of that scheduling period, using the data of each MBS session carried on the MCH corresponding to the PMCH. It then determines a set of PMCH time slots within that scheduling period based on the index of the time slot-beam mapping method, and transmits the set of TBs through the set of PMCH time slots.

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