CN115589619A

CN115589619A - Method for switching multicast service transmission mode and related equipment

Info

Publication number: CN115589619A
Application number: CN202110756672.5A
Authority: CN
Inventors: 刘潇蔓; 柴丽
Original assignee: China Mobile Communications Group Co Ltd; China Mobile Communications Ltd Research Institute
Current assignee: China Mobile Communications Group Co Ltd; China Mobile Communications Ltd Research Institute
Priority date: 2021-07-05
Filing date: 2021-07-05
Publication date: 2023-01-10
Also published as: WO2023280149A1

Abstract

A method for switching transmission modes of multicast services and related equipment are provided, the method comprises: the base station determines whether a transmission mode of the first multicast service of the first terminal needs to be switched, wherein the transmission mode comprises the following types: shared transmission mode or MRB transmission, and dedicated transmission mode or DRB transmission; and under the condition that the first multicast service needs to be converted from the first transmission mode to the second transmission mode, the base station triggers to establish or bind a core network tunnel related to the second transmission mode through the first terminal, or the base station directly requests the core network to establish or bind the core network tunnel related to the second transmission mode. The embodiment of the invention can realize the transmission conversion process between the MRB and the DRB in the terminal multicast service receiving process, and can realize the switching between the target side and the source side which do not simultaneously support the multicast transmission by the terminal or dynamically change the transmission mode in the cell supporting the multicast transmission.

Description

Method for switching multicast service transmission mode and related equipment

Technical Field

The present invention relates to the field of mobile communications technologies, and in particular, to a method and a related device for switching multicast service transmission modes.

Background

Multicast/broadcast is a technology for transmitting data from a data source to a plurality of target mobile terminals, which realizes the sharing of network (including core network and access network) resources, improves network resources, especially the utilization rate of air interface resources, and the current multicast service reception is usually realized by connecting a terminal with a serving cell.

In the prior art, the multicast service is carried through a shared core network tunnel or a user-specific (UE-specific) independent core network tunnel, which is determined by the core network or a higher application layer. Therefore, the triggered network element (such as the core network) has complete end-to-end bearer establishment information. On the other hand, the multicast service reception in the prior art is usually realized by connecting a serving cell to a terminal, so that there is a scenario that a user equipment (UE, also referred to as a terminal) switches from a cell supporting multicast transmission to another cell not supporting multicast transmission, and vice versa. In the above scenario, it is necessary to trigger a change of a multicast service transmission mode by the UE, that is, the Radio side is converted from an MBMS Point-to-Multipoint Radio Bearer (MRB) to a Data Radio Bearer (DRB) or vice versa, which may occur during or before and after handover, but at any time, a trigger/decision of the Radio side is required, and then the current Radio side does not have complete end-to-end Bearer establishment information, so that it is difficult to implement the above conversion process.

Disclosure of Invention

At least one embodiment of the present invention provides a method and a related device for switching a multicast service transmission mode, which can implement switching of the multicast service transmission mode on a wireless side.

According to an aspect of the present invention, at least one embodiment provides a method for switching transmission modes of a multicast service, which is applied to a base station, and includes:

the base station determines whether a transmission mode of the first multicast service of the first terminal needs to be switched, wherein the transmission mode comprises the following steps: shared transmission mode or MRB transmission, and dedicated transmission mode or DRB transmission;

under the condition that the first multicast service needs to be converted from a first transmission mode to a second transmission mode, the base station triggers to establish or bind a core network tunnel related to the second transmission mode through a first terminal, or the base station directly requests a core network to establish or bind the core network tunnel related to the second transmission mode; the core network tunnel refers to an end-to-end transmission channel between the first terminal and the core network.

Further, in accordance with at least one embodiment of the present invention, the base station includes a DU and a CU;

the base station determines whether a transmission mode of a first multicast service of a first terminal needs to be switched, and the method comprises the following steps:

the DU judges whether the transmission mode of the first multicast service of the first terminal needs to be switched according to at least one of the channel quality indication, the HARQ feedback information and the transmission mode switching request message of the UE sent by the first terminal, and sends first indication information for indicating the switching of the transmission mode to the CU through an F1 port uplink signaling when the transmission mode needs to be switched.

and the CU judges whether the transmission mode of the first multicast service of the first terminal needs to be switched or not according to at least one of the channel quality indication of the first terminal, the HARQ feedback information and the transmission mode switching request message of the UE reported by the DU.

Further, in accordance with at least one embodiment of the present invention, the first transmission mode is a shared transmission mode or MRB, and the second transmission mode is a dedicated transmission mode or DRB; the base station triggers, through the first terminal, establishment or binding of a core network tunnel related to the second transmission mode, including:

the CU sends a first RRC signaling to the first terminal, wherein the first RRC signaling is used for triggering the first terminal to establish the core network tunnel aiming at a second transmission mode of the first multicast service;

the CU receives second indication information sent by a core network, wherein the second indication information is used for indicating a first transmission channel between the core network and the CU, and the first transmission channel is a transmission channel between the core network and the CU, which is established by the core network according to the trigger of the first terminal and aiming at a second transmission mode of the first multicast service;

and the CU sends a first user context modification message aiming at the first terminal to the DU according to the second indication information, and sends a second RRC signaling to the first terminal, establishes a first DRB and converts the first multicast service of the first terminal from the current MRB to the first DRB.

Further, in accordance with at least one embodiment of the present invention, the first transmission mode is a shared transmission mode or MRB, and the second transmission mode is a dedicated transmission mode or DRB; the base station directly requests a core network to establish or bind the core network tunnel related to the second transmission mode, including:

a CU sends a first request message carrying first terminal identification information to a core network, wherein the first request message requests the core network to establish a second transmission channel between the core network and the CU aiming at a second transmission mode of the first multicast service;

a CU receives a first response message which is sent by a core network and carries a first NAS message, wherein the first NAS message is the NAS message which is sent to the core network when a first terminal initially accesses a first multicast service;

the CU sends a second user context modification message for the first terminal to the DU, and sends a third RRC signaling to the first terminal, establishes a first DRB, and switches the first multicast service of the first terminal from the current MRB to the first DRB.

Further, according to at least one embodiment of the present invention, further comprising:

the CU stores a first NAS message which is sent to a core network when the first terminal initially accesses a first multicast service;

and when the CU sends the first request message, the CU also carries the first NAS message in the first request message.

Further, in accordance with at least one embodiment of the present invention, there is also provided:

when the CU saves the first NAS message, setting a corresponding timer and starting timing;

when the CU receives the first indication information, whether the timer is overtime is judged:

if the timer is not overtime, the first request message is sent;

if the timer is overtime, sending a fourth RRC signaling to the first terminal, wherein the fourth RRC signaling is used for triggering the first terminal to establish the core network tunnel aiming at a second transmission mode of the first multicast service; third indication information of the core network received by the CU, where the third indication information is used to indicate a second transmission channel between the core network and the CU, and the second transmission channel is a transmission channel between the core network and the CU, which is established by the core network according to the trigger of the first terminal for a second transmission mode of the first multicast service; the CU sends a third user context modification message for the first terminal to the DU, and sends fifth RRC signaling to the first terminal, establishes the first DRB, and switches the first multicast service of the first terminal from the current MRB to the first DRB.

Further, in accordance with at least one embodiment of the present invention, the first transmission mode is a dedicated transmission mode or DRB, and the second transmission mode is a shared transmission mode or MRB; the base station triggers, through the first terminal, establishment or binding of a core network tunnel related to the second transmission mode, including:

if the current serving cell of the first terminal has established the MRB of the first multicast service, the CU sends a fourth user context modification message for the first terminal to the DU, so that the DU sends a sixth RRC signaling to the first terminal, where the sixth RRC signaling is used to convert the first multicast service of the first terminal from the current DRB to the MRB;

and if the current service cell of the first terminal does not establish the MRB of the first multicast service, the CU sends a seventh RRC signaling to the first terminal, wherein the seventh RRC signaling is used for indicating the first terminal to establish the MRB of the first multicast service and join a multicast group of the first multicast service through a multicast joining process.

in case that the transmission mode of the first multicast service of the first terminal is MRB, the method further includes:

a CU receives terminal related information of a first terminal reported by a DU, wherein the terminal related information is related information of a decision basis of an MRB transmission mode, and the MRB transmission mode comprises PTP and/or PTM;

the CU judges whether to perform MRB transmission mode conversion of the first multicast service of the first terminal according to the terminal related information of the first terminal, and sends fourth indication information for indicating the MRB transmission mode conversion to the DU when the fact that the MRB transmission mode conversion is required is judged;

the DU converts the MRB transmission mode of the first multicast service according to the fourth indication information and sends a response message to the CU;

and the CU receives the response message and sends a seventh RRC signaling to the first terminal, wherein the seventh RRC signaling is used for indicating the first terminal to switch the MRB transmission mode of the first multicast service.

Further, according to at least one embodiment of the present invention, the fourth indication information is further used for indicating at least one of the following information: an RLC mode of the converted MRB transmission mode, and a retention time of the duplicate transmission; wherein the RLC mode comprises an acknowledged mode and an unacknowledged mode;

the response message is a downlink data transmission state message, or the response message is a maximum F1-U sequence number carrying a data packet which is successfully sent to a lower layer by the MRB transmission mode before conversion;

the seventh RRC signaling carries a reset parameter of the RLC receiving window of the terminal determined according to the RLC mode of the converted MRB transmission mode.

the DU judges whether to carry out the conversion of the MRB transmission mode of the first multicast service of the first terminal according to the terminal related information of the first terminal, wherein the terminal related information is the relevant information according to which the decision of the MRB transmission mode is based, and the MRB transmission mode comprises PTP and/or PTM;

when the DU judges that the conversion of the MRB transmission mode is required, the DU sends fifth indication information for indicating the conversion of the MRB transmission mode to the CU;

the CU detects whether a GTP-U tunnel corresponding to the converted MRB transmission mode exists or not according to the fifth indication information, if so, the CU sends sixth indication information to the DU and sends an eighth RRC signaling to the first terminal so as to convert the MRB transmission mode of the first multicast service of the first terminal; if the MRB transmission mode does not exist, initiating the building process of the GTP-U tunnel corresponding to the converted MRB transmission mode, after the GTP-U tunnel is successfully built, sending seventh indication information to the DU, and sending a ninth RRC signaling to the first terminal so as to convert the MRB transmission mode of the first multicast service of the first terminal.

According to another aspect of the present invention, at least one embodiment provides a base station comprising:

a decision module, configured to determine whether a transmission mode of a first multicast service of a first terminal needs to be switched, where the transmission mode includes the following types: shared transmission mode or MRB transmission, and, dedicated transmission mode or DRB transmission;

a conversion processing module, configured to trigger, by a first terminal, establishment or binding of a core network tunnel related to a second transmission mode when the first multicast service needs to be converted from a first transmission mode to the second transmission mode, or directly request a core network to establish or bind the core network tunnel related to the second transmission mode; the core network tunnel refers to an end-to-end transmission channel between the first terminal and the core network.

Further, in accordance with at least one embodiment of the present invention, the base station includes a DU and a CU; the decision module is arranged in the DU;

the decision module is further configured to determine whether a transmission mode of a first multicast service of the first terminal needs to be switched according to at least one of a channel quality indication, HARQ feedback information, and a transmission mode switching request message of the UE sent by the first terminal, and send first indication information for indicating switching of the transmission mode to the CU through the F1 port uplink signaling when it is determined that the transmission mode needs to be switched.

Further in accordance with at least one embodiment of the present invention, the base station includes a DU and a CU; the CU is provided with the decision module;

the decision module is further configured to determine whether a transmission mode of a first multicast service of the first terminal needs to be switched according to at least one of a channel quality indicator of the first terminal reported by the DU, HARQ feedback information, and a transmission mode switching request message of the UE.

Further, in accordance with at least one embodiment of the present invention, the first transmission mode is a shared transmission mode or MRB transmission, and the second transmission mode is a dedicated transmission mode or DRB transmission;

the conversion processing module is arranged in the CU;

the switching processing module is further configured to send a first RRC signaling to the first terminal when the first terminal triggers to establish or bind the core network tunnel related to the second transmission mode, where the first RRC signaling is used to trigger the first terminal to establish the core network tunnel for the second transmission mode of the first multicast service; receiving second indication information sent by a core network, wherein the second indication information is used for indicating a first transmission channel between the core network and a CU, and the first transmission channel is a transmission channel between the core network and the CU, which is established by the core network according to a second transmission mode of the first multicast service and triggered by the first terminal; and sending a first user context modification message aiming at the first terminal to the DU according to the second indication information, and sending a second RRC signaling to the first terminal, establishing a first DRB and converting the first multicast service of the first terminal from the current MRB to the first DRB.

Further, in accordance with at least one embodiment of the present invention, the first transmission mode is a shared transmission mode or MRB, and the second transmission mode is a dedicated transmission mode or DRB;

the conversion processing module is arranged in the CU;

the conversion processing module is further configured to send a first request message carrying first terminal identification information to a core network when the core network is directly requested to establish or bind a core network tunnel related to the second transmission mode, where the first request message requests the core network to establish a second transmission channel between the core network and the CU for the second transmission mode of the first multicast service; receiving a first response message which is sent by a core network and carries a first NAS message, wherein the first NAS message is the NAS message which is sent to the core network when the first terminal initially accesses the first multicast service; and sending a second user context modification message aiming at the first terminal to the DU, sending a third RRC signaling to the first terminal, establishing a first DRB, and converting the first multicast service of the first terminal from the current MRB to the first DRB.

a storage module, configured to store a first NAS message sent to a core network when the first terminal initially accesses the first multicast service;

when the conversion processing module sends the first request message, the first request message also carries the first NAS message.

the timing module is used for setting a corresponding timer and starting timing when the first NAS message is stored;

the conversion processing module is further configured to determine whether the timer is overtime when receiving the first indication information:

if the timer is not overtime, the first request message is sent;

if the timer is overtime, sending a fourth RRC signaling to the first terminal, wherein the fourth RRC signaling is used for triggering the first terminal to establish the core network tunnel aiming at the second transmission mode of the first multicast service; third indication information of the core network received by the CU, where the third indication information is used to indicate a second transmission channel between the core network and the CU, and the second transmission channel is a transmission channel between the core network and the CU, which is established by the core network according to the trigger of the first terminal for a second transmission mode of the first multicast service; the CU sends a third user context modification message for the first terminal to the DU, and sends fifth RRC signaling to the first terminal, establishes the first DRB, and switches the first multicast service of the first terminal from the current MRB to the first DRB.

Further, according to at least one embodiment of the present invention, the first transmission mode is a dedicated transmission mode or DRB, and the second transmission mode is a shared transmission mode or MRB;

the conversion processing module is arranged in the CU;

the conversion processing module is further configured to, when the first terminal triggers establishment or binding of the core network tunnel related to the second transmission mode:

Further, in accordance with at least one embodiment of the present invention, the base station includes a DU and a CU; the CU is provided with the decision module;

the decision module is further configured to receive terminal related information of the first terminal reported by the DU when the transmission mode of the first multicast service of the first terminal is MRB, where the terminal related information is information related to a decision basis of the MRB transmission mode, and the MRB transmission mode includes PTP and/or PTM; judging whether to perform MRB transmission mode conversion of the first multicast service of the first terminal according to the terminal related information of the first terminal, and sending fourth indication information for indicating the MRB transmission mode conversion to the DU when the MRB transmission mode conversion is required to be performed;

the DU is used for converting the MRB transmission mode of the first multicast service according to the fourth indication information and sending a response message to the CU;

and the CU is used for receiving the response message and sending a seventh RRC signaling to the first terminal, wherein the seventh RRC signaling is used for indicating the first terminal to switch the MRB transmission mode of the first multicast service.

Further, according to at least one embodiment of the present invention, the fourth indication information is further used for indicating at least one of the following information: RLC mode of the MRB transmission mode after the transition, and, duplicating the retention time of the transmission; wherein the RLC mode comprises an acknowledged mode and an unacknowledged mode;

the response message is a downlink data transmission state message, or the response message carries the maximum F1-U sequence number of a data packet successfully sent to a lower layer by the MRB transmission mode before conversion;

Further in accordance with at least one embodiment of the present invention, the base station includes a DU and a CU; the DU is provided with the decision module;

the decision module is further configured to determine whether to perform a MRB transmission mode switching of the first multicast service of the first terminal according to terminal related information of the first terminal, where the terminal related information is information related to a decision basis of the MRB transmission mode, and the MRB transmission mode includes PTP and/or PTM; when the conversion of the MRB transmission mode is judged to be needed, fifth indication information used for indicating the conversion of the MRB transmission mode is sent to the CU;

the CU is configured to detect whether a GTP-U tunnel corresponding to the converted MRB transmission mode exists according to the fifth indication information, and if the GTP-U tunnel exists, send sixth indication information to the DU and send an eighth RRC signaling to the first terminal to convert the MRB transmission mode of the first multicast service of the first terminal; and if the MRB transmission mode does not exist, initiating the establishment process of the GTP-U tunnel corresponding to the converted MRB transmission mode, after the GTP-U tunnel is successfully established, sending seventh indication information to the DU, and sending a ninth RRC signaling to the first terminal so as to convert the MRB transmission mode of the first multicast service of the first terminal.

According to another aspect of the present invention, at least one embodiment provides a base station comprising: a processor, a memory and a program stored on the memory and executable on the processor, which when executed by the processor implements the steps of the method as described above.

According to another aspect of the invention, at least one embodiment provides a computer readable storage medium having a program stored thereon, which when executed by a processor, performs the steps of the method as described above.

Compared with the prior art, the method and the related device for switching the transmission mode of the multicast service provided by the embodiment of the invention can realize the transmission switching process between the MRB and the DRB in the terminal multicast service receiving process, and can realize the switching between the target side and the source side which do not simultaneously support the multicast transmission by the terminal or dynamically change the transmission mode in the cell supporting the multicast transmission.

Drawings

Various additional advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the invention. Also, like reference numerals are used to refer to like parts throughout the drawings. In the drawings:

fig. 1 is a schematic view of an application scenario according to an embodiment of the present invention;

FIG. 2 is a diagram illustrating an arrangement of a decision layer according to an embodiment of the present invention;

FIG. 3 is a schematic diagram of another arrangement of a decision layer according to an embodiment of the present invention;

FIG. 4 is a schematic diagram illustrating another arrangement of a decision layer according to an embodiment of the present invention;

fig. 5 is a flowchart of a method for switching transmission modes of a multicast service according to an embodiment of the present invention;

fig. 6 is a schematic structural diagram of a base station according to an embodiment of the present invention;

fig. 7 is another schematic structural diagram of a base station according to an embodiment of the present invention.

Detailed Description

Exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

The terms first, second and the like in the description and in the claims of the present application are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used is interchangeable under appropriate circumstances such that the embodiments of the application described herein are, for example, capable of operation in sequences other than those illustrated or otherwise described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus. In the description and in the claims "and/or" means at least one of the connected objects.

The techniques described herein are not limited to NR systems and Long Time Evolution (LTE)/LTE Evolution (LTE-Advanced) systems, and may also be used for various wireless communication systems, such as Code Division Multiple Access (CDMA), time Division Multiple Access (TDMA), frequency Division Multiple Access (FDMA), orthogonal Frequency Division Multiple Access (OFDMA), single carrier Frequency Division Multiple Access (SC-FDMA), and other systems. The terms "system" and "network" are often used interchangeably. CDMA systems may implement Radio technologies such as CDMA2000, universal Terrestrial Radio Access (UTRA), and so on. UTRA includes Wideband CDMA (WCDMA) and other CDMA variants. TDMA systems may implement radio technologies such as Global System for Mobile communications (GSM). The OFDMA system may implement radio technologies such as Ultra Mobile Broadband (UMB), evolved-UTRA (E-UTRA), IEEE 802.21 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, flash-OFDM, etc. UTRA and E-UTRA are parts of the Universal Mobile Telecommunications System (UMTS). LTE and higher LTE (e.g., LTE-A) are new UMTS releases that use E-UTRA. UTRA, E-UTRA, UMTS, LTE-A and GSM are described in the literature from an organization named "third Generation Partnership project" (3 rd Generation Partnership project,3 GPP). CDMA2000 and UMB are described in documents from an organization named "third generation partnership project 2" (3 GPP 2). The techniques described herein may be used for both the above-mentioned systems and radio technologies, as well as for other systems and radio technologies. However, the following description describes the NR system for purposes of example, and NR terminology is used in much of the description below, although the techniques may also be applied to applications other than NR system applications.

The following description provides examples, and does not limit the scope, applicability, or configuration set forth in the claims. Changes may be made in the function and arrangement of elements discussed without departing from the spirit and scope of the disclosure. Various examples may omit, substitute, or add various procedures or components as appropriate. For example, the described methods may be performed in an order different than described, and various steps may be added, omitted, or combined. Additionally, features described with reference to certain examples may be combined in other examples.

Referring to fig. 1, fig. 1 is a block diagram of a wireless communication system to which an embodiment of the present invention is applicable. The wireless communication system includes a terminal 11 and a network device 12. The terminal 11 may also be referred to as a User terminal or a User Equipment (UE), and the terminal 11 may be a Mobile phone, a Tablet Personal Computer (Tablet Personal Computer), a Laptop Computer (Laptop Computer), a Personal Digital Assistant (PDA), a Mobile Internet Device (MID), a Wearable Device (Wearable Device), or a vehicle-mounted Device, and the specific type of the terminal 11 is not limited in the embodiment of the present invention. The network device 12 may be a Base Station and/or a core network element, wherein the Base Station may be a 5G or later-version Base Station (e.g., a gNB, a 5G NR NB, etc.), or a Base Station in other communication systems (e.g., an eNB, a WLAN access point, or other access points, etc.), where the Base Station may be referred to as a node B, an evolved node B, an access point, a Base Transceiver Station (BTS), a radio Base Station, a radio Transceiver, a Basic Service Set (BSS), an Extended Service Set (ESS), a node B, an evolved node B (eNB), a home node B, a home evolved node B, a WLAN access point, a WiFi node, or some other suitable terminology in the field, as long as the same technical effect is achieved, the Base Station is not limited to a specific technical vocabulary, and it should be noted that the Base Station in the NR system is only taken as an example in the embodiment of the present invention, but the specific type of the Base Station is not limited.

The base stations may communicate with the terminals 11 under the control of a base station controller, which may be part of the core network or some of the base stations in various examples. Some base stations may communicate control information or user data with the core network through a backhaul. In some examples, some of the base stations may communicate with each other, directly or indirectly, over backhaul links, which may be wired or wireless communication links. A wireless communication system may support operation on multiple carriers (waveform signals of different frequencies). A multi-carrier transmitter can transmit modulated signals on the multiple carriers simultaneously. For example, each communication link may be a multi-carrier signal modulated according to various radio technologies. Each modulated signal may be transmitted on a different carrier and may carry control information (e.g., reference signals, control channels, etc.), overhead information, data, and so on.

The base station may communicate wirelessly with the terminal 11 via one or more access point antennas. Each base station may provide communication coverage for a respective coverage area. The coverage area of an access point may be divided into sectors that form only a portion of the coverage area. A wireless communication system may include base stations of different types (e.g., macro, micro, or pico base stations). The base stations may also utilize different radio technologies, such as cellular or WLAN radio access technologies. The base stations may be associated with the same or different access networks or operator deployments. The coverage areas of different base stations (including coverage areas of base stations of the same or different types, coverage areas utilizing the same or different radio technologies, or coverage areas belonging to the same or different access networks) may overlap.

The communication links in a wireless communication system may comprise an Uplink for carrying Uplink (UL) transmissions (e.g., from terminal 11 to network device 12) or a Downlink for carrying Downlink (DL) transmissions (e.g., from network device 12 to terminal 11). The UL transmission may also be referred to as reverse link transmission, while the DL transmission may also be referred to as forward link transmission. Downlink transmissions may be made using licensed frequency bands, unlicensed frequency bands, or both. Similarly, uplink transmissions may be made using licensed frequency bands, unlicensed frequency bands, or both.

As described in the background art, the wireless side in the prior art does not have information of complete end-to-end bearer establishment, and therefore, it is difficult to implement switching of multicast service transmission modes. In addition, in a transmission scheme switching scenario, the transmission scheme may also exist in a certain cell supporting multicast service, and therefore it is desirable that the wireless side can dynamically change the transmission scheme for the UE according to the UE requirements and the like so as to meet the QoS requirements of the UE. Particularly, under the architecture of central unit-distributed unit (CU-DU), there is a specific scheme for how the wireless side triggers the above-mentioned switching process and how to implement the switching procedure, and in addition, there is no scheme disclosed for the dynamic switching of the transmission modes of multicast transmission (PTM and PTP) at present.

In order to solve at least one of the above problems, embodiments of the present invention provide a method for switching a multicast service transmission mode, which can implement switching of a multicast service transmission mode on a wireless side.

In the embodiment of the present invention, for the Multicast Service, a sublayer/function module exists in a network side protocol stack for deciding/converting a transmission mode of the Multicast Service, which includes an initial transmission mode in a transmission range of a UE/cell/Multicast Broadcast Service (MBS), such as a DRB (dedicated transmission mode) or an MRB (shared transmission mode), in particular. In the embodiment of the present invention, the MRB may further include a decision to determine whether to be a point-to-point (PTP) or a point-to-multipoint (PTM) mode, and further includes a decision to dynamically switch PTP/PTM and/or a switch between MBR (shared delivery mode) and DRB (independent delivery mode) during the UE service reception, where the sub-layer may be a virtual sub-layer/function located in another layer, or may be a separate sub-layer.

In the CU-DU architecture, the decision layer/decision module may be located in the CU and/or DU, and fig. 2 to 4 are examples of possible locations thereof, and the decision layer/decision module described above is represented by the decision layer in fig. 2 to 4. Fig. 2 to fig. 4 only identify the case that the decision layer is mostly an independent sublayer, but it can also belong to a sublayer as a certain functional module, for example, the decision layer can belong to PDCP, i.e. as a part of PDCP layer, when it is in CU, or belong to RLC/MAC, i.e. as a part of RLC/MAC layer, when it is in DU.

Referring to fig. 5, a method for switching a multicast service transmission mode according to an embodiment of the present invention includes:

step 21, the base station determines whether it is necessary to switch the transmission mode of the first multicast service of the first terminal, where the transmission mode includes the following types: shared transmission mode or MRB transmission, and dedicated transmission mode or DRB transmission.

Here, whether the transmission mode of the first multicast service needs to be switched may be determined by a decision module (which may also be referred to as a decision layer) in the base station. The transmission modes include a shared transmission mode (shared transmission mode) which is mapped to the MRB on the radio side and is therefore sometimes referred to as MRB transmission, and an individual transmission mode (dedicated transmission mode) which is mapped to the DRB on the radio side and is therefore sometimes referred to as DRB transmission. The first multicast service may be a multicast, broadcast or multicast service.

Step 22, when the first multicast service needs to be switched from the first transmission mode to the second transmission mode, the base station triggers, through the first terminal, establishment or binding of a core network tunnel related to the second transmission mode, or the base station directly requests the core network to establish or bind the core network tunnel related to the second transmission mode.

Here, the core network tunnel refers to an end-to-end transmission channel between the first terminal and the core network. When the transmission mode of the first multicast service needs to be switched, for example, when the current first transmission mode is switched to the second transmission mode, the base station may trigger, through the first terminal, establishment or binding of a core network tunnel related to the second transmission mode, or the base station directly sends a request to the core network to establish or bind the core network tunnel related to the second transmission mode.

Through the steps, the embodiment of the invention realizes the conversion of the multicast service transmission mode at the wireless side.

The above steps are described in detail below with reference to different configurations of the base station and different deployment modes of the decision modules.

1. In the CU-DU architecture, the decision module (decision layer) is located in the DU

In the CU-DU architecture, the base station includes a DU and a CU, and when the decision module is located in the DU, in step 21, the DU determines whether a transmission mode of a first multicast service of the first terminal needs to be switched according to at least one of a channel quality indication, HARQ feedback information, and a transmission mode switching request message of the UE sent by the first terminal, and sends first indication information for indicating switching of the transmission mode to the CU through an F1 port uplink signaling when it is determined that the transmission mode needs to be switched.

For example, the DU side determines whether to change the UE transmission scheme based on CQI reporting or HARQ feedback (statistics) of the UE or a request of the UE, and mainly considers the handover between the MRB and the DRB. The decision may be based on a criterion configured by the OAM/CN/CU, where the criterion may include information such as a period/non-periodicity of information collection, a decision threshold, a threshold available duration, and so on, for example, UE HARQ feedback periodically collected according to configuration is counted, and then the decision is made based on the configured threshold. After the decision of DU, the DU may be indicated to the CU through F1 port uplink signaling, which may be included in the existing F1 port signaling, such as adding an IE in the UE CONTEXT MODIFICATION request (UE CONTEXT MODIFICATION request), or indicated through new signaling.

In step 22, after receiving the decision of the DU, the CU may process the DU in the following manner:

1)MRB->DRB:

here, it is assumed that the first transmission mode is a shared transmission mode or MRB transmission, and the second transmission mode is a dedicated transmission mode or DRB transmission. At this time, the CU may implement the establishment of the DRB in one of the following two ways.

Mode 1: and the CU triggers and establishes or binds the core network tunnel related to the second transmission mode through the first terminal.

The CU sends a first RRC signaling to the first terminal, wherein the first RRC signaling is used for triggering the first terminal to establish the core network tunnel (an end-to-end transmission channel between the terminal and the core network) aiming at the second transmission mode of the first multicast service; then, the CU receives second indication information sent by a core network, wherein the second indication information is used for indicating a first transmission channel between the core network and the CU, and the first transmission channel is a transmission channel between the core network and the CU, which is established by the core network according to the trigger of the first terminal and aiming at a second transmission mode of the first multicast service; then, the CU sends a first user context modification message for the first terminal to the DU according to the second indication information, and sends a second RRC signaling to the first terminal, establishes a first DRB, and switches the first multicast service of the first terminal from the current MRB to the first DRB. Here, the first DRB is a DRB corresponding to the second transmission mode of the first multicast service.

The process specifically comprises the following steps:

a) And the CU sends a first RRC signaling to the first terminal, wherein the first RRC signaling is used for triggering the first terminal to establish an end-to-end transmission channel between the terminal and the core network aiming at the second transmission mode of the first multicast service. Here, the end-to-end path includes a transmission path between the core network and the wireless side, and a transmission path between the wireless side and the first terminal. The first RRC signaling may be a new RRC signaling or an RRC reconfiguration or an RRC release message, and its function is mainly to instruct the UE to trigger an end-to-end transmission channel with the first multicast service.

B) After receiving the first RRC signaling of the CU, the UE initiates a DRB establishment request, which includes an NAS message to be sent to the core network (if an RRC release message is received, RRC connection establishment is re-initiated), and possibly, the UE may indicate that the DRB request establishment cause is related to multicast transmission, or carries a multicast service identifier, such as a TMGI, which carries a PDU Session ID allocated by an MRB corresponding to the DRB requested to be established, a source multicast IP address corresponding to the MRB, shared tunnel information corresponding to the MRB, and the like. And the core network establishes a transmission channel between the core network and the CU aiming at the second transmission mode of the first multicast service according to the NAS message.

C) And the core network sends second indication information to the CU, wherein the second indication information is used for indicating a first transmission channel between the core network and the wireless side to the CU. And the CU receives second indication information sent by the core network.

D) And the CU establishes a first DRB according to the received second indication information of the core network. Specifically, the CU sends a first user CONTEXT MODIFICATION message (UE CONTEXT MODIFICATION) for the first terminal to the DU, and sends a second RRC signaling (for example, RRC reconfiguration message) to the first terminal, establishes the first DRB, and converts the first multicast service of the first terminal from the current MRB to the first DRB. The second RRC signaling may include DRB related configuration, such as PDCP, RLC, MAC, and configuration of the physical layer.

Here, the CU establishes a protocol stack on the RAN side by sending UE CONTEXT MODIFICATION to the DU, and sends an RRC reconfiguration message to the first terminal to establish a protocol stack on the UE side, thereby finally establishing the first DRB. In addition, the NAS message carries session (session) related information (i.e., channel information established by the CN, which is transparently transmitted by the base station).

Mode 2: the CU directly requests the core network to establish or bind the core network tunnel related to the second transmission mode.

The CU sends a first request message carrying first terminal identification information to a core network, wherein the first request message requests the core network to establish a second transmission channel between the core network and the CU for a first terminal aiming at a second transmission mode of the first multicast service; a CU receives a first response message which is sent by a core network and carries a first NAS message, wherein the first NAS message is the NAS message which is sent to the core network when a first terminal initially accesses a first multicast service; and the CU sends a second user context modification message aiming at the first terminal to the DU, sends a third RRC signaling to the first terminal, establishes a first DRB and converts the first multicast service of the first terminal from the current MRB to the first DRB.

The process specifically comprises the following steps:

a) When the first terminal initially accesses the multicast service (join process), the CU retains the NAS message passed through by the UE to the CN, and optionally, a corresponding timer may be set for the retained UE NAS message, that is, the CU can use the NAS message only before the timer expires.

B) After receiving the transmission mode conversion decision sent by the DU, if the timer is not timed out, the CU sends the UE identification information (e.g., AMF UE NGAP ID, RAN UE NGAP ID) such as the reserved NAS message and UE ID to the CN, and requests the CN to establish a transmission channel. If the time is out, the establishment of the DRB is triggered through the procedure in the above mode 1.

Similarly, the CN side may retain the NAS message of the first terminal, and the CU sends only one request message to the CN at this time.

C) And the CN sends a response message to reply the request of the CU after establishing a second transmission channel between the CN and the CU according to the request of the CU, wherein the response message can carry a corresponding NAS message.

D) And the CU sends UE CONTEXT MODIFICATION aiming at the first terminal to the DU, and sends an RRC reconfiguration message to the first terminal to transfer the transmission of the first multicast service of the first terminal from the MRB to the newly-built first DRB.

Here, the CU establishes a protocol stack on the RAN side by sending UE CONTEXT MODIFICATION to the DU, and sends an RRC reconfiguration message to the first terminal to establish a protocol stack on the first terminal side, thereby finally establishing the first DRB. In addition, the NAS message carries session (session) related information (i.e., channel information established by the CN, which is transparently transmitted by the base station).

In the foregoing process, the CU may store a first NAS message that is sent to a core network when the first terminal initially accesses the first multicast service. In addition, when the CU sends the first request message, the CU may also carry the first NAS message in the first request message.

Further, the CU sets a corresponding timer and starts timing when saving the first NAS message. In this way, when the CU receives the first indication information, it may determine whether the timer has timed out:

a) If the timer is not overtime, the first request message is sent;

b) If the timer is overtime, sending a fourth RRC signaling to the first terminal, wherein the fourth RRC signaling is used for triggering the first terminal to establish the core network tunnel aiming at a second transmission mode of the first multicast service; third indication information of the core network received by the CU, where the third indication information is used to indicate a second transmission channel between the core network and the CU, and the second transmission channel is a transmission channel between the core network and the CU, which is established by the core network according to the trigger of the first terminal and for a second transmission mode of the first multicast service; the CU sends a third user context modification message for the first terminal to the DU, and sends fifth RRC signaling to the first terminal, establishes the first DRB, and switches the first multicast service of the first terminal from the current MRB to the first DRB.

2)DRB->MRB:

Here, it is assumed that the first transmission mode is a shared transmission mode or DRB, and the second transmission mode is a dedicated transmission mode or MRB. Then:

in step 22, the CU triggers, through the first terminal, establishment or binding of the core network tunnel related to the second transmission mode, which may specifically include:

a) The current service cell has established MRB/shared delivery mode

b) The current serving cell does not establish MRB/shared delivery mode

2. In the CU-DU architecture, the decision module (decision layer) is located in the CU

In the CU-DU architecture, the base station includes a DU and a CU, and when the decision module is located in the CU, in step 21, the CU determines whether to switch the transmission mode of the first multicast service of the first terminal according to at least one of a channel quality indication of the first terminal, HARQ feedback information, and a transmission mode switching request message of the UE, which are reported by the DU. Or, when the first terminal is switched, the CU decides whether the transmission mode conversion is needed or not according to a decision criterion provided by OAM/CN and the like.

When the CU decides to carry out transmission mode conversion, the CU detects whether NAS information of the first terminal is reserved, if the NAS information is reserved, the CU can directly request the core network to trigger establishment of a related channel, otherwise, the CU triggers establishment or binds of a core network tunnel related to the second transmission mode through the first terminal, and then sends a corresponding RRC reconfiguration message to the first terminal to realize conversion of a transmission mode. For specific implementation manners of MRB- > DRB and DRB- > MRB, please refer to the description in the first item above, which is not repeated herein.

3. Integrated base station

The method is also applicable to the case of an integrated base station, and the base station makes a decision on the transmission mode of the UE based on a certain criterion and establishes the relevant channel by triggering the UE or directly requesting the core network.

The following describes switching of transmission modes in MRB (switching of PTP and PTM).

For the specific transmission mode problem under MRB, when the decision layer is located on CU or on DU RLC layer, the decision layer may decide not only the transmission mode of a certain UE, but also the transmission mode in the whole cell.

Under the CU-DU architecture, in the embodiments of the present invention, when the transmission mode of the first multicast service of the first terminal is MRB, the MRB transmission mode may be switched, where the MRB transmission mode includes PTP and/or PTM. Specifically, the decision may be made per UE or per cell to determine whether the MRB transmission mode needs to be switched.

A. Decision making Per UE (decision of Per UE)

1) The decision layer is located in the CU

And under the condition that the transmission mode of the first multicast service of the first terminal is MRB, the CU receives terminal related information of the first terminal reported by the DU, wherein the terminal related information is related information according to the decision of the MRB transmission mode. Then, the CU determines whether to perform the MRB transmission mode switching of the first multicast service of the first terminal according to the terminal related information of the first terminal, and transmits fourth instruction information for instructing the MRB transmission mode switching to the DU when it is determined that the MRB transmission mode switching is necessary. Then, the DU switches the MRB transmission mode of the first multicast service according to the fourth indication information, and sends a response message to the CU. And the CU receives the response message and sends a seventh RRC signaling to the first terminal, wherein the seventh RRC signaling is used for indicating the first terminal to switch the MRB transmission mode of the first multicast service.

Here, the fourth indication information is further used to indicate at least one of the following information: an RLC mode of the converted MRB transmission mode, and a retention time of the duplicate transmission; wherein the RLC mode comprises an acknowledged mode and an unacknowledged mode;

the response message is a downlink data transmission state message, or the response message is a maximum F1-U sequence number carrying a data packet which is successfully sent to a lower layer by the MRB transmission mode before conversion; the F1-U serial number refers to the user plane serial number of the interface between the central unit and the distribution unit.

Specifically, the criterion for the decision of switching the MRB transmission mode may be generated by OAM or CN network and sent to CU, or generated by CU autonomously. The decision is based on one or more information that may include the number of users receiving some or all multicast services in the cell, service QoS requirements, UE PTM/PTP leg channel quality, network resources/busy/idle conditions, UE requests, UE uplink feedback (PDCP status report, ARQ feedback, CQI), and related statistics. Based on different decision bases, the DU needs to report the relevant information of the UE to the CU correspondingly, such as UE request, UE uplink feedback (PDCP status report, ARQ feedback, CQI), and relevant statistics.

When the CU decides to perform PTP/PTM conversion for the first terminal, the CU needs to send related indication information to the DU, indicating that the PTM is switched to PTP, or PTP is switched to PTM, or duplicate transmission is performed or duplicate transmission is cancelled, and possibly the CU may further indicate an RLC mode of a transmission path (leg) after conversion (e.g., PTM only supports unacknowledged mode UM, PTP may support UM or acknowledged mode AM), and information of a retention time of leg after conversion. The indication information can be carried by UE CONTEXT MODIFICATION REQUEST of the F1 interface; or corresponding indication bit carrying is added in the packet header of the F1 port data packet; or indicating the GTP-U tunnel condition corresponding to the corresponding PTP/PTM leg temporarily through the tunnel establishment process.

After the DU receives the decision of the CU, the DU feeds back UE CONTEXT MODIFICATION RESPONSE to the CU, wherein the maximum F1-U SN corresponding to the packet successfully sent to the lower layer by the current leg can be carried, and/or feeds back a Downlink Data Delivery Status message to carry the maximum F1-U SN or other more information.

After receiving the feedback of the DU, the CU sends an RRC reconfiguration message to the first terminal, and possibly determines whether the RLC receiving window related parameters of the first terminal need to be reset according to the new leg RLC mode.

2) The decision layer is located in DU

Under the condition that the transmission mode of the first multicast service of the first terminal is MRB, the DU judges whether to switch the MRB transmission mode of the first multicast service of the first terminal according to terminal related information of the first terminal, wherein the terminal related information is the decision basis related information of the MRB transmission mode, and the MRB transmission mode comprises PTP and/or PTM; when the DU judges that the conversion of the MRB transmission mode is needed, fifth indication information for indicating the conversion of the MRB transmission mode is sent to the CU; the CU detects whether a GTP-U tunnel corresponding to the MRB transmission mode after conversion exists or not according to the fifth indication information, if yes, sixth indication information is sent to the DU, and eighth RRC signaling is sent to the first terminal so as to convert the MRB transmission mode of the first multicast service of the first terminal; and if the MRB transmission mode does not exist, initiating the establishment process of the GTP-U tunnel corresponding to the converted MRB transmission mode, after the GTP-U tunnel is successfully established, sending seventh indication information to the DU, and sending a ninth RRC signaling to the first terminal so as to convert the MRB transmission mode of the first multicast service of the first terminal.

Specifically, the criteria for the PTP/PTM conversion decision may be that OAM, CN network, or CU generates and issues to DU, or DU generates autonomously, and the decision may include one or more information of the number of users receiving some or all multicast services in the cell, service QoS requirements, UE PTM/PTP leg channel quality, network resource/busy/idle conditions, UE request, UE uplink feedback (PDCP status report, ARQ feedback, CQI), and related statistics.

When the DU decides to perform PTP/PTM conversion for a certain UE, the DU needs to send a relevant indication to the CU, where the indication is to switch from PTM to PTP, or from PTP to PTM, or to perform duplicate transmission or cancel duplicate transmission, and possibly the DU may also indicate the RLC mode in which the leg is transmitted after conversion, the retention time of the leg after conversion, and other information. The message can be carried by UE CONTEXT MODIFICATION REQUERED of the F1 interface, and can also carry the maximum F1-U SN corresponding to the packet successfully sent by the current leg to the lower layer, or can be carried by adding a corresponding indication bit in the Downlink Data Delivery Status of the F1 interface.

After receiving the decision of the DU, the CU needs to detect whether there is a GTP-U tunnel corresponding to the corresponding PTP and/or PTM link, and if not, the CU needs to initiate a corresponding tunnel establishment procedure first. Then, the CU sends corresponding reception feedback to the DU (for example, the reception feedback is carried by a UE CONTEXT MODIFICATION response message), and interacts with the tunnel information of the new leg, and the like. In addition, the CU also sends an RRC reconfiguration message to the first terminal, configuring the switching of the transmission mode.

B. Decision making Per cell (decision of Per cell)

For the cell-level transport mode decision, there is a decision layer at least above the RLC layer of the DU or in the CU, which does not exclude that there is also a decision layer within the DU. The intra-CU transport mode transition decision for a cell may be based on statistics of at least one of the following: the filtering result of the layer three of the UE, or one or more items of information reported by the DU, such as a request of the UE, uplink feedback (PDCP status report, ARQ feedback, CQI) of the UE and related statistics, or a decision for per UE in the DU.

As can be seen from the above description, the embodiments of the present invention can implement a transmission switching process between the MRB and the DRB in terminal multicast service reception, and can implement a handover between a target side and a source side that do not support multicast transmission simultaneously by a terminal, or dynamically change a transmission mode in a cell that supports multicast transmission.

Various methods of embodiments of the present invention have been described above. An apparatus for carrying out the above method is further provided below.

An embodiment of the present invention provides a base station shown in fig. 6, including:

a decision module 61, configured to determine whether a transmission mode of the first multicast service of the first terminal needs to be switched, where the transmission mode includes the following types: shared transmission mode or MRB transmission, and, dedicated transmission mode or DRB transmission;

a conversion processing module 62, configured to, when the first multicast service needs to be converted from the first transmission mode to the second transmission mode, trigger, by the base station, to establish or bind the core network tunnel related to the second transmission mode through the first terminal, or directly request the core network to establish or bind the core network tunnel related to the second transmission mode; the core network tunnel refers to an end-to-end transmission channel between the first terminal and the core network.

Preferably, the base station includes a DU and a CU; the decision module is arranged in the DU;

Preferably, the base station includes a DU and a CU; the CU is provided with the decision module;

the decision module is further configured to determine whether to switch the transmission mode of the first multicast service of the first terminal according to at least one of a channel quality indicator of the first terminal, HARQ feedback information, and a transmission mode switching request message of the UE reported by the DU.

Preferably, the first transmission mode is a shared transmission mode or MRB transmission, and the second transmission mode is a dedicated transmission mode or DRB transmission;

the conversion processing module is arranged in the CU;

the switching processing module is further configured to send a first RRC signaling to the first terminal when the first terminal triggers to establish or bind the core network tunnel related to the second transmission mode, where the first RRC signaling is used to trigger the first terminal to establish the core network tunnel for the second transmission mode of the first multicast service; receiving second indication information sent by a core network, wherein the second indication information is used for indicating a first transmission channel between the core network and a CU, and the first transmission channel is a transmission channel between the core network and the CU, which is established by the core network according to a second transmission mode of the first multicast service and triggered by the first terminal; and sending a first user context modification message aiming at the first terminal to the DU according to the second indication information, and sending a second RRC signaling to the first terminal, establishing a first DRB corresponding to the current MRB of the first multicast service and converting the first multicast service of the first terminal from the current MRB to the first DRB.

the conversion processing module is arranged in the CU;

Preferably, the base station further includes:

a storage module, configured to store a first NAS message that is sent to a core network when the first terminal initially accesses the first multicast service;

Preferably, the base station further includes:

if the timer is not overtime, the first request message is sent;

if the timer is overtime, sending a fourth RRC signaling to the first terminal, wherein the fourth RRC signaling is used for triggering the first terminal to establish the core network tunnel aiming at the second transmission mode of the first multicast service; third indication information of the core network received by the CU, where the third indication information is used to indicate a second transmission channel between the core network and the CU, and the second transmission channel is a transmission channel between the core network and the CU, which is established by the core network according to the trigger of the first terminal for a second transmission mode of the first multicast service; the CU sends a third user context modification message for the first terminal to the DU, and sends a fifth RRC signaling to the first terminal, establishes the first DRB and converts the first multicast service of the first terminal from the current MRB to the first DRB.

Preferably, the first transmission mode is a dedicated transmission mode or a DRB, and the second transmission mode is a shared transmission mode or an MRB;

the conversion processing module is arranged in the CU;

the decision module is further configured to receive, when the transmission mode of the first multicast service of the first terminal is MRB, terminal-related information of the first terminal reported by the DU, where the terminal-related information is information related to a decision basis of the MRB transmission mode, and the MRB transmission mode includes PTP and/or PTM; judging whether to perform MRB transmission mode conversion of the first multicast service of the first terminal according to the terminal related information of the first terminal, and sending fourth indication information for indicating the MRB transmission mode conversion to the DU when the MRB transmission mode conversion is required to be performed;

Preferably, the fourth indication information is further used for indicating at least one of the following information: an RLC mode of the converted MRB transmission mode, and a retention time of the duplicate transmission; wherein the RLC mode comprises an acknowledged mode and an unacknowledged mode;

the decision module is further configured to determine whether to switch the MRB transmission mode of the first multicast service of the first terminal according to terminal-related information of the first terminal, where the terminal-related information is information related to a decision basis of the MRB transmission mode, and the MRB transmission mode includes PTP and/or PTM; when the conversion of the MRB transmission mode is needed, sending fifth indication information for indicating the conversion of the MRB transmission mode to the CU;

the CU is configured to detect whether a GTP-U tunnel corresponding to the converted MRB transmission mode exists according to the fifth indication information, and if the GTP-U tunnel exists, send sixth indication information to the DU and send an eighth RRC signaling to the first terminal to convert the MRB transmission mode of the first multicast service of the first terminal; and if the MRB transmission mode does not exist, initiating the establishment process of the GTP-U tunnel corresponding to the converted MRB transmission mode, after the GTP-U tunnel is successfully established, sending seventh indication information to the DU, and sending a ninth RRC signaling to the first terminal so as to convert the MRB transmission mode of the first multicast service of the first terminal. It should be noted that the apparatus in this embodiment is a device corresponding to the method shown in fig. 5, and the implementation manners in the above embodiments are all applicable to the embodiment of this device, and the same technical effects can be achieved. It should be noted that the apparatus provided in the embodiment of the present invention can implement all the method steps implemented by the method embodiment, and can achieve the same technical effects, and detailed descriptions of the same parts and beneficial effects as the method embodiment in this embodiment are omitted here.

Referring to fig. 7, an embodiment of the present invention provides a structural diagram of a base station, including: a processor 701, a transceiver 702, a memory 703 and a bus interface, wherein:

in the embodiment of the present invention, the base station further includes: a program stored on a memory 703 and executable on a processor 701, which when executed by the processor 701 performs the steps of:

the base station determines whether a transmission mode of the first multicast service of the first terminal needs to be switched, wherein the transmission mode comprises the following steps: shared transmission mode or MRB, and dedicated transmission mode or DRB;

It can be understood that, in the embodiment of the present invention, when being executed by the processor 701, the computer program can implement the processes of the method embodiment shown in fig. 5, and can achieve the same technical effect, and in order to avoid repetition, the description is omitted here.

In FIG. 7, the bus architecture may include any number of interconnected buses and bridges, with various circuits representing one or more processors, in particular processor 701, and memory, in particular memory 703 being linked together. The bus architecture may also link together various other circuits such as peripherals, voltage regulators, power management circuits, and the like, which are well known in the art, and therefore, will not be described any further herein. The bus interface provides an interface. The transceiver 702 may be a plurality of elements including a transmitter and a receiver that provide a means for communicating with various other apparatus over a transmission medium.

The processor 701 is responsible for managing the bus architecture and general processing, and the memory 703 may store data used by the processor 701 in performing operations.

It should be noted that the terminal in this embodiment is a device corresponding to the method shown in fig. 5, and the implementation manners in the above embodiments are all applied to the embodiment of the terminal, and the same technical effects can be achieved. In the device, the transceiver 702 and the memory 703, and the transceiver 702 and the processor 701 may be communicatively connected through a bus interface, the function of the processor 701 may also be implemented by the transceiver 702, and the function of the transceiver 702 may also be implemented by the processor 701. It should be noted that, the apparatus provided in the embodiment of the present invention can implement all the method steps implemented by the method embodiment and achieve the same technical effect, and detailed descriptions of the same parts and beneficial effects as the method embodiment in this embodiment are omitted here.

In some embodiments of the invention, there is also provided a computer readable storage medium having a program stored thereon, the program when executed by a processor implementing the steps of:

the base station determines whether a transmission mode of a first multicast service of a first terminal needs to be switched, wherein the transmission mode comprises the following steps: shared transmission mode or MRB, and dedicated transmission mode or DRB;

and under the condition that the first multicast service needs to be converted from the first transmission mode to the second transmission mode, the base station triggers to establish or bind the core network tunnel related to the second transmission mode through the first terminal, or the base station directly requests the core network to establish or bind the core network tunnel related to the second transmission mode.

When executed by the processor, the program can implement all implementation manners in the above method for converting the multicast service transmission mode applied to the base station, and can achieve the same technical effect, and is not described herein again to avoid repetition.

Those of ordinary skill in the art will appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present invention.

It is clear to those skilled in the art that, for convenience and brevity of description, the specific working processes of the above-described systems, apparatuses and units may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again.

In the embodiments provided in the present application, it should be understood that the disclosed apparatus and method may be implemented in other ways. For example, the above-described apparatus embodiments are merely illustrative, and for example, the division of the units is only one logical division, and other divisions may be realized in practice, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may be in an electrical, mechanical or other form.

The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one position, or may be distributed on multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiments of the present invention.

In addition, functional units in the embodiments of the present invention may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit.

The functions may be stored in a computer-readable storage medium if they are implemented in the form of software functional units and sold or used as separate products. Based on such understanding, the technical solution of the present invention may be embodied in the form of a software product, which is stored in a storage medium and includes instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present invention. And the aforementioned storage medium includes: various media capable of storing program codes, such as a U disk, a removable hard disk, a ROM, a RAM, a magnetic disk, or an optical disk.

The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily think of the changes or substitutions within the technical scope of the present invention, and shall cover the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A method for switching transmission modes of multicast services is applied to a base station, and is characterized by comprising the following steps:

the base station determines whether a transmission mode of the first multicast service of the first terminal needs to be switched, wherein the transmission mode comprises the following types: shared transmission mode or MRB transmission, and dedicated transmission mode or DRB transmission;

2. The method of claim 1, wherein the base station comprises a distribution unit, DU, and a central unit, CU;

3. The method of claim 1, wherein the base station comprises a DU and a CU;

and the CU judges whether the transmission mode of the first multicast service of the first terminal needs to be switched or not according to at least one of the channel quality indication of the first terminal, the HARQ feedback information and the transmission mode switching request message of the UE, which are reported by the DU.

4. The method of claim 2 or 3, wherein the first transmission mode is a shared transmission mode or MRB transmission, and the second transmission mode is a dedicated transmission mode or DRB transmission; the base station triggers, through the first terminal, establishment or binding of a core network tunnel related to the second transmission mode, including:

a CU receives second indication information sent by a core network, wherein the second indication information is used for indicating a first transmission channel between the core network and the CU, and the first transmission channel is a transmission channel between the CU and the core network, which is established by the core network according to a second transmission mode of the first multicast service and triggered by the first terminal;

5. The method of claim 2 or 3, wherein the first transmission mode is a shared transmission mode or MRB, and the second transmission mode is a dedicated transmission mode or DRB; the base station directly requests a core network to establish or bind the core network tunnel related to the second transmission mode, including:

and the CU sends a second user context modification message aiming at the first terminal to the DU, sends a third RRC signaling to the first terminal, establishes a first DRB and converts the first multicast service of the first terminal from the current MRB to the first DRB.

6. The method of claim 5, further comprising:

the CU stores a first NAS message sent to a core network when the first terminal initially accesses a first multicast service;

7. The method of claim 6, further comprising:

and when the CU receives the first indication information, judging whether the timer is overtime:

if the timer is not overtime, the first request message is sent;

8. The method of claim 2 or 3, wherein the first transmission mode is a dedicated transmission mode or a DRB, and the second transmission mode is a shared transmission mode or an MRB; the base station triggers, through the first terminal, establishment or binding of a core network tunnel related to the second transmission mode, including:

and if the current service cell of the first terminal does not establish the MRB of the first multicast service, the CU sends a seventh RRC signaling to the first terminal, wherein the seventh RRC signaling is used for indicating the first terminal to establish the MRB of the first multicast service and join the multicast group of the first multicast service through a multicast joining process.

9. The method of claim 1, wherein the base station comprises a DU and a CU;

in the case that the transmission mode of the first multicast service of the first terminal is MRB, the method further includes:

the CU judges whether to carry out MRB transmission mode conversion of the first multicast service of the first terminal according to the terminal related information of the first terminal, and sends fourth indication information for indicating the MRB transmission mode conversion to the DU when judging that the MRB transmission mode conversion is needed;

10. The method of claim 9,

the fourth indication information is further used for indicating at least one of the following information: RLC mode of the MRB transmission mode after the transition, and, duplicating the retention time of the transmission; wherein the RLC modes include an acknowledged mode and an unacknowledged mode;

the response message is a downlink data transmission state message, or the response message is a user plane F1-U serial number carrying an interface between the largest central unit and the distribution unit of the data packet successfully sent to the lower layer by the MRB transmission mode before conversion;

11. The method of claim 1, wherein the base station comprises a DU and a CU;

the DU judges whether to switch the MRB transmission mode of the first multicast service of the first terminal according to the terminal related information of the first terminal, wherein the terminal related information is the decision basis related information of the MRB transmission mode, and the MRB transmission mode comprises PTP and/or PTM;

when the DU judges that the conversion of the MRB transmission mode is needed, fifth indication information for indicating the conversion of the MRB transmission mode is sent to the CU;

the CU detects whether a GTP-U tunnel corresponding to the MRB transmission mode after conversion exists or not according to the fifth indication information,

if the first multicast service exists, sending sixth indication information to the DU, and sending an eighth RRC signaling to the first terminal so as to convert the MRB transmission mode of the first multicast service of the first terminal; or, if the MRB transmission mode does not exist, initiating a process of establishing a GTP-U tunnel corresponding to the converted MRB transmission mode, and after the GTP-U tunnel is successfully established, sending seventh indication information to the DU, and sending a ninth RRC signaling to the first terminal, so as to convert the MRB transmission mode of the first multicast service of the first terminal.

12. A base station, comprising:

13. The base station of claim 12, wherein the base station comprises a DU and a CU; the decision module is arranged in the DU;

14. The base station of claim 12, wherein the base station comprises a DU and a CU; the CU is provided with the decision module;

15. The base station of claim 13 or 14, wherein the first transmission mode is a shared transmission mode or MRB transmission, and the second transmission mode is a dedicated transmission mode or DRB transmission;

the conversion processing module is arranged in the CU;

the switching processing module is further configured to send a first RRC signaling to the first terminal when the first terminal triggers to establish or bind the core network tunnel related to the second transmission mode, where the first RRC signaling is used to trigger the first terminal to establish the core network tunnel for the second transmission mode of the first multicast service; receiving second indication information sent by a core network, wherein the second indication information is used for indicating a first transmission channel between the core network and a CU, and the first transmission channel is a transmission channel between the core network and the CU, which is established by the core network according to a second transmission mode of the first multicast service and triggered by the first terminal; and sending a first user context modification message aiming at the first terminal to the DU according to the second indication information, sending a second RRC signaling to the first terminal, establishing a first DRB corresponding to the current MRB of the first multicast service, and converting the first multicast service of the first terminal from the current MRB to the first DRB.

16. The base station of claim 13 or 14, wherein the first transmission mode is a shared transmission mode or MRB transmission, and the second transmission mode is a dedicated transmission mode or DRB transmission;

the conversion processing module is arranged in the CU;

17. The base station of claim 16, further comprising:

18. The base station of claim 17, further comprising:

the conversion processing module is further configured to, when receiving the first indication information, determine whether the timer is overtime:

if the timer is not overtime, the first request message is sent;

if the timer is overtime, sending a fourth RRC signaling to the first terminal, wherein the fourth RRC signaling is used for triggering the first terminal to establish the core network tunnel aiming at a second transmission mode of the first multicast service; third indication information of the core network received by the CU, where the third indication information is used to indicate a second transmission channel between the core network and the CU, and the second transmission channel is a transmission channel between the core network and the CU, which is established by the core network according to the trigger of the first terminal for a second transmission mode of the first multicast service; the CU sends a third user context modification message for the first terminal to the DU, and sends a fifth RRC signaling to the first terminal, establishes the first DRB and converts the first multicast service of the first terminal from the current MRB to the first DRB.

19. The base station of claim 13 or 14, wherein the first transmission mode is a dedicated transmission mode or DRB, and the second transmission mode is a shared transmission mode or MRB;

the conversion processing module is arranged in the CU;

20. The base station of claim 12, wherein the base station comprises a DU and a CU; the CU is provided with the decision module;

the decision module is further configured to receive terminal related information of the first terminal reported by the DU when the transmission mode of the first multicast service of the first terminal is MRB, where the terminal related information is information related to a decision basis of the MRB transmission mode, and the MRB transmission mode includes PTP and/or PTM; judging whether to perform MRB transmission mode conversion of the first multicast service of the first terminal according to the terminal related information of the first terminal, and sending fourth indication information for indicating the MRB transmission mode conversion to the DU when the MRB transmission mode conversion is judged to be required;

21. The base station of claim 20,

the fourth indication information is further used for indicating at least one of the following information: an RLC mode of the converted MRB transmission mode, and a retention time of the duplicate transmission; wherein the RLC mode comprises an acknowledged mode and an unacknowledged mode;

22. The base station of claim 12, wherein the base station comprises a DU and a CU; the decision module is arranged in the DU;

the decision module is further configured to determine whether to perform a MRB transmission mode switching of the first multicast service of the first terminal according to terminal related information of the first terminal, where the terminal related information is information related to a decision basis of the MRB transmission mode, and the MRB transmission mode includes PTP and/or PTM; when the conversion of the MRB transmission mode is needed, sending fifth indication information for indicating the conversion of the MRB transmission mode to the CU;

the CU is configured to detect whether a GTP-U tunnel corresponding to the converted MRB transmission mode exists according to the fifth indication information, and if the GTP-U tunnel exists, send sixth indication information to the DU and send an eighth RRC signaling to the first terminal to convert the MRB transmission mode of the first multicast service of the first terminal; if the MRB transmission mode does not exist, initiating the building process of the GTP-U tunnel corresponding to the converted MRB transmission mode, after the GTP-U tunnel is successfully built, sending seventh indication information to the DU, and sending a ninth RRC signaling to the first terminal so as to convert the MRB transmission mode of the first multicast service of the first terminal.

23. A base station, comprising: processor, memory and program stored on the memory and executable on the processor, which when executed by the processor implements the steps of the method according to any of claims 1 to 11.

24. A computer-readable storage medium, characterized in that a computer program is stored on the computer-readable storage medium, which computer program, when being executed by a processor, carries out the steps of the method according to any one of claims 1 to 11.