WO2013000300A1

WO2013000300A1 - Td-lte based wideband digital cluster system and data transmission method thereof

Info

Publication number: WO2013000300A1
Application number: PCT/CN2012/073059
Authority: WO
Inventors: 杜高鹏; 马子江; 张现周; 朱永升
Original assignee: 中兴通讯股份有限公司
Priority date: 2011-06-30
Filing date: 2012-03-26
Publication date: 2013-01-03
Also published as: CN102857873B; CN102857873A

Abstract

The present invention provides a TD-LTE based wideband digital cluster system and a data transmission method thereof. The system comprises: one or more cluster application servers, for scheduling a cluster service, scheduling and managing an end-to-end session of a user terminal, and sending data from the user terminal to an LTE core network; the LTE core network, for receiving data, allocating an IP multicast address for the session according to a group identifier of a target terminal group, sending the IP multicast address to a radio access sub-system, and sending the data to an evolved NodeB joining IP multicast corresponding to the IP multicast address; and the radio access sub-system, comprising: one or more evolved NodeBs, for joining IP multicast corresponding to the IP multicast address according to the IP multicast address, receiving data, and sending the data to each target terminal in the target terminal group. By means of the present invention, the existing LTE core network can be extended to implement the cluster service.

Description

The present invention relates to the field of communications, and in particular to a broadband digital based on Time Division-Long Term Evolution (TD-LTE). Cluster system and its data transmission method. BACKGROUND OF THE INVENTION Currently, trunking communication systems are widely used in the fields of government departments, public safety, emergency telecommunications, electric power, civil aviation, petrochemicals, and military facilities. With the development of communication technology and the deepening of people's understanding of the cluster system, the cluster system plays an increasingly important role as an efficient emergency command and dispatch system. The development of the cluster system has experienced the stage of the analog cluster system and the narrowband digital trunk system. Among them, the cluster system of the two development stages has many drawbacks. For example, the analog cluster system has the disadvantages of large interference, many blind spots and limited frequency; narrow band Although the digital trunking system has improved communication quality and capacity relative to the analog clustering system, it is still weak in terms of data transmission capability and multimedia service support capability, and the narrowband digital trunking system is based on Long Term Evolution (Long Term Evolution, The broadband digital trunking system referred to as LTE) has certain difficulties in the evolution process. How to use the existing LTE network to implement cluster services, and no effective solution has been given in the related technologies. SUMMARY OF THE INVENTION Embodiments of the present invention provide a broadband digital trunking system based on TD-LTE and a cluster service transmission method thereof to solve at least the above problems. According to an embodiment of the present invention, a TD-LTE-based broadband digital trunking system is provided, including: one or more cluster application servers, configured to schedule cluster services, and schedule and manage end-to-end sessions of user terminals, which will come from The data of the user terminal is sent to the LTE core network, and the LTE core network is configured to receive the data, and allocate an IP multicast address to the session according to the group identifier of the target terminal group of the data, and Sending the IP multicast address to the radio access subsystem, and then sending the data to the evolved base station that joins the IP multicast corresponding to the IP multicast address; the radio access subsystem includes: one or more The evolved base station is configured to add IP multicast corresponding to the IP multicast address according to the IP multicast address, receive the data sent by the LTE core network, and send the data to the target Each target terminal in the terminal group. Preferably, the radio access subsystem further includes: an MCE; the LTE core network includes: a P-GW, a BM-SC, an MBMS-GW, and an MME; wherein the P-GW is configured to receive the data And determining, when the received data is the data of the cluster service in the multicast mode, forwarding the data to the BM-SC; the BM-SC, configured to send a session open request message to the MBMS-GW, Instructing the MBMS service transmission to start; the MBMS-GW is configured to create an MBMS bearer context for the session, and send a session open request message to the MME; the MME is configured to receive the session open request message, The session creates an MBMS bearer context, and sends a session open request to the MCE in its jurisdiction, where the session open request carries an IP multicast address of the session; the MCE is set to be Assigning a time-frequency resource to the session, establishing a service bearer, and transmitting a session open request message to the one or more evolved base stations within its jurisdiction; the one or more evolved base stations are configured to transmit the MBMS service Establish radio resources and configure radio bearers transmitted by MBSFN. Preferably, the MBMS-GW is further configured to allocate the IP multicast address to the session according to a list of downlink data stream nodes that it saves, and carry the IP multicast address in a location sent to the MME In the session open request message. Preferably, the MME is further configured to allocate the IP multicast address according to the evolved information to which each target terminal in the target terminal group belongs. Preferably, the LTE core network further includes: an HSS, configured to store subscription information of the cluster user terminal; the MME is further configured to acquire, from the HSS, subscription information of each target terminal corresponding to the group identifier Determining information of the evolved base station to which each of the target terminals belongs according to the subscription information acquired from the HSS. Preferably, the MME is further configured to obtain, from the subscription information reported by the cluster user terminal, information about an evolved base station to which each target terminal belongs. Advantageously, the system further comprises: an IMS subsystem configured to forward data between the one or more cluster application servers and the LTE core network. Preferably, the system further includes: an operation and maintenance subsystem, configured to manage the cluster user terminal, and configure parameters of the wireless access subsystem and devices in the LTE core network. Preferably, the one or more cluster application servers comprise: an application server based on a push-to-talk over PoC, and an application server based on a global open cluster structure Gota. According to another embodiment of the present invention, a data transmission method for a broadband digital trunking system based on TD-LTE is provided, including: after an end-to-end session establishment of a user terminal, the cluster application server will data from the user terminal Sending to the LTE core network; the LTE core network receives the data, assigns an IP multicast address to the session according to the group identifier of the target terminal group of the data, and sends the IP multicast address to the wireless connection An evolved base station that enters the subsystem; the evolved base station adds an IP multicast corresponding to the IP multicast address according to the IP multicast address; the LTE core network sends the data to join the IP The evolved base station of the IP multicast corresponding to the multicast address; the evolved base station receives the data sent by the LTE core network, and sends the data to each target terminal in the target terminal group. Preferably, the LTE core network receives the data, allocates an IP multicast address to the session according to the group identifier of the target terminal group of the data, and sends the IP multicast address to the wireless access subsystem, including The P-GW of the LTE core network receives the data, and when determining that the received data is data of a cluster service, forwarding the data to a BM-SC of the LTE core network; the BM-SC direction The MBMS-GW of the LTE core network sends a session open request message, indicating that the MBMS service transmission is about to start; the MBMS-GW creates an MBMS bearer context for the session for transmitting the MBMS service, and sends the MBMS bearer context to the MME of the LTE core network. a session open request message; the MME receives the session open request message, creates an MBMS bearer context for the session for transmitting the MBMS service, and sends a session open to an MCE of the radio access subsystem within its jurisdiction The request, where the session open request carries the IP multicast address of the session. Preferably, the MCE allocates a time-frequency resource to the session, establishes a service bearer, and sends a session open request message to the one or more evolved base stations in its jurisdiction; the one or more evolved base stations Establishing a radio resource for the MBMS service transmission, and configuring a radio bearer transmitted by the MBSFN. Preferably, before the MBMS-GW sends a session open request message to the MME, the method further includes: the MBMS-GW assigning the IP multicast to the session according to the saved downlink data flow node list An address, and the IP multicast address is carried in the session open request message sent to the MME. Preferably, before the MME sends a session open request to the MCE of the radio access subsystem in its jurisdiction, the method further includes: the MME according to the evolution of each target terminal in the target terminal group Type information is assigned to the IP multicast address. Preferably, the MME obtains the evolved information to which each target terminal belongs according to the following manner: the MME obtains subscription information of each target terminal corresponding to the group identifier from the LTE core network HSS, according to the The subscription information acquired by the HSS determines an evolved base station to which each of the target terminals belongs Or the MME obtains information about the evolved base station to which the target terminal belongs from the subscription information reported by the cluster user terminal. With the present invention, the cluster application server and the LTE system are combined to implement the cluster service, and the existing digital network device can be realized by using the existing LTE network without adding a new network element device, thereby reducing the cost and improving the LTE. Network utilization. BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are set to illustrate,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, 1 is a schematic structural diagram of a TD-LTE-based broadband digital trunking system according to Embodiment 1 of the present invention; FIG. 2 is a schematic structural diagram of a TD-LTE-based broadband digital trunking system according to Embodiment 2 of the present invention; 3 is a schematic structural diagram of a TD-LTE-based broadband digital trunking system according to Embodiment 3 of the present invention; FIG. 4 is a flowchart of a data transmission method of a TD-LTE-based broadband data clustering system according to Embodiment 4 of the present invention; . BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. It should be noted that the embodiments in the present application and the features in the embodiments may be combined with each other without conflict. Embodiment 1 FIG. 1 is a schematic structural diagram of a TD-LTE-based broadband digital trunking system according to an embodiment of the present invention. As shown in FIG. 1 , the TD-LTE-based broadband digital trunking system of the embodiment of the present invention mainly includes three parts: one or more cluster application servers 10, an LTE core network 20, and a wireless access subsystem 30. One or more cluster application servers 10 are configured to schedule cluster services, establish an end-to-end session with the user terminal, and send data from the user terminal to the LTE core network 20; the LTE core network 20 is configured to receive The data, according to the group identifier of the target terminal group of the data, assign an IP multicast address to the session, and send the IP multicast address to the wireless access subsystem 30, and then send the data to the joining office. The evolved base station (evolved Node B, referred to as e B) of the IP multicast corresponding to the IP multicast address; the wireless access subsystem 30 includes: The one or more evolved base stations 300 are configured to join the IP multicast corresponding to the IP multicast address according to the IP multicast address, receive the data sent by the LTE core network 20, and send the data. To each target terminal in the target terminal group. The IP multicast address may be allocated by a Multimedia Broadcast Multicast Service-Gateway (MBMS-GW) of the LTE core network, or may be a Mobility Management Entity of the LTE core network. Referred to as MME). The foregoing system provided by the embodiment of the present invention can increase the cost of the broadband digital trunking service by using the existing LTE network by adding a function module for processing the cluster service in the existing LTE core network, thereby reducing the cost and improving the LTE network. Utilization rate. Embodiment 2 FIG. 2 is a schematic structural diagram of a TD-LTE-based broadband digital trunking system according to Embodiment 2 of the present invention. As shown in FIG. 2, in this embodiment, the wireless access subsystem 30 further includes: a primary communication device. (Master Communication Equipment, MCE for short) 302; LTE core network 20 includes: P-GW (Packet Data Network Gateway) 200, BM-SC (Broadcast Multicast Service Center) 202, MBMS-GW 204 and MME 206. In this embodiment, the P-GW 200 is configured to receive data from the cluster application server 10, and when determining that the received data is data of the cluster mode in the multicast mode, forward the data to the BM-SC 202; BM-SC 202, configured to send a session open request message to the MBMS-GW 204, indicating that the MBMS service transmission is about to start; the MBMS-GW 204, configured to create an MBMS bearer context for the session for transmitting the MBMS service, and send the MBMS bearer context to the MME 206 a session open request message; the MME 206, configured to receive the session open request message, create an MBMS bearer context for the session for transmitting the MBMS service, and send a session open request to the MCE 302 within its jurisdiction, where The session open request carries the IP multicast address of the session; the MCE 302 is configured to allocate time-frequency resources for the session, establish a service bearer, and send the one or more evolved base stations 300 within its jurisdiction. Transmitting a session open request message; one or more evolved base stations 300 are configured to establish a radio resource for the MBMS service transmission, and configure no MBSFN transmission Bearer. In another preferred embodiment of the present embodiment, if the P-GW 200 determines that the received data is data of a unicast cluster service, the data is forwarded to the S-GW for processing, and the specific processing flow is in the existing LTE system. The processing flow of the non-clustered service data is the same and will not be described here. In a preferred embodiment of the embodiment of the present invention, the MBMS-GW 204 is further configured to allocate the IP multicast address to the session according to a list of downlink data stream nodes (ie, a distribution tree) that it holds, and The IP multicast address is carried in the session open request message sent to the MME. In another preferred embodiment of the embodiment of the present invention, the MME 206 is further configured to allocate the IP multicast address according to the evolved information to which each target terminal in the target terminal group belongs. In another preferred embodiment of the present invention, the LTE core network 20 further includes: a Home Subscriber Server (HSS) 208, configured to store subscription information of the cluster user terminal, and the MME 206 is further configured to The subscription information of each of the target terminals corresponding to the group identifier is obtained from the HSS 208, and the information of the evolved base station to which each of the target terminals belongs is determined according to the subscription information acquired from the HSS. In another preferred embodiment of the present invention, the MME 206 is further configured to obtain, from the subscription information reported by the cluster user terminal, information about the evolved base station to which each of the target terminals belongs. For example, the cluster user terminal can report its subscription information through NAS messages. In the foregoing Embodiments 1 and 2, the foregoing system provided by the embodiment of the present invention may further include: an IP Multimedia Subsystem (IMS), configured to be in the one or more cluster application servers and the Data is forwarded between LTE core networks. In the foregoing Embodiments 1 and 2, the system provided by the embodiment of the present invention may further include: an operation and maintenance subsystem, configured to manage the cluster user terminal, and configure the wireless access subsystem and the LTE core network. The parameters of the device in . In the foregoing Embodiments 1 and 2, one or more cluster application servers 10 include, but are not limited to: a PTT Over Cellular (PoC)-based application server, based on a global open cluster architecture (Global open Trunking) Architecture, referred to as Gota) application server. Embodiment 3 FIG. 3 is a schematic structural diagram of a TD-LTE-based broadband digital trunking system according to Embodiment 3 of the present invention. As shown in FIG. 3, in the embodiment of the present invention, a TD-LTE-based broadband digital trunking system mainly includes : Terminal, Broadband Wireless Access Subsystem, Network Subsystem, IMS, Application Subsystem, and Operation and Maintenance Subsystem. The architecture of the TD-LTE based broadband digital trunking system of this embodiment will be described below. In this embodiment, the terminal includes but is not limited to: a handheld terminal, a radio station, a fixed station, and a wireless dispatching station. In this embodiment, the broadband wireless access subsystem is composed of multiple eNodeBs (evolved base stations), and multiple eNodeBs can be connected through the X2 interface. In addition to supporting existing functions, the eNodeB has a built-in eNodeB in order to support the cluster function. Support for cluster modules with weakened faults, including analog signaling units and analog media sheets In the two parts of the element, the analog signaling unit mainly performs the processing and loopback of the signaling, and the analog media unit mainly completes the forwarding and loopback of the media data. In a preferred embodiment of the present embodiment, the broadband wireless access subsystem may further include an MCE, which is responsible for time-frequency resource scheduling on the wireless interface. The MCE and the eNodeB can be connected through the M2 interface. In this embodiment, the handheld mobile station, the radio station, the fixed station, and the wireless dispatching station can share the radio resources with the broadband wireless access subsystem through the LTE-Uu interface. In this embodiment, the network subsystem (corresponding to the LTE core network in Embodiments 1 and 2) includes but is not limited to: MME, SGW, HSS, BM-SC, MBMS-GW, and P-GW. The MME processes the control node of the interaction between the terminal and the network subsystem signaling. In order to support the cluster function, a module supporting the cluster service needs to be newly added. The module completes the information about the storage cluster user terminal, and is responsible for acquiring the cluster user terminal from the HSS. Signing information and dynamically generating a distribution tree (ie IP multicast address) of the information of the cluster terminal.

The HSS stores the home subscription information of the terminal user. In order to support the cluster function, a module for supporting the cluster service needs to be added. The module stores the eNodeB information of the UE and the group identifier (TMGI-ID) to which the UE belongs, and stores the {group Identification, group service distribution area information, terminal list information}.

The S-GW is the end point of the media data interface connecting the wireless broadband access subsystem, and is mainly responsible for the routing and forwarding of data packets.

The P-GW is responsible for the terminal IP address allocation and the QoS guarantee, and the traffic-based charging according to the rules. In order to support the cluster function, a module supporting the cluster service needs to be added. The module can be based on a single call (general bearer) or a group call. (Each cluster service group is assigned a TMGI identifier), and whether downlink data is distributed to the S-GW or BM-SC, whether unicast mode or multicast mode is selected.

The BM-SC is responsible for the joining of terminal requests, scheduling of sessions, and the like. In order to support the cluster function, only the parameters related to the cluster service are configured when creating the MBMS context, and the parameters that are not related to the cluster are not concerned.

The MBMS-GW is an entry for broadcast/multicast services, broadcasts packets to eNodeBs in all service areas, and is responsible for MBMS sessions. In this embodiment, the MME can be connected to the SGW through the S11 interface, connected to the HSS through the S6a interface, and connected to the BM-SC through the Sm interface; and the SGW can be connected to the P-GW through the S5 interface, the BM-SC It can be connected to the P-GW through the SGi interface, and the BM-SC can be connected to the MBMS-GW through the SGmb and SGimb interfaces. The eNodeB is connected to the MBMS-GW through the M1 interface, and the MCE is connected to the MME through the M3 interface. In this embodiment, the application subsystem mainly includes a cluster application server, completes the scheduling function of the cluster service, and is connected to the P-GW. The cluster application server includes but is not limited to: a PoC-based application server, a Gota-based cluster application server, and other types of cluster application servers. In order to support the cluster service, the architecture uses the PoC server to cooperate to complete the utterance control function in the cluster. If the other application server can perform the extended session control function, the IMS does not need to go through the IMS. Otherwise, the IMS needs to be arranged in this embodiment. . In this embodiment, the operation and maintenance subsystem includes a main function of managing user data, and can perform operations such as opening an account of a cluster user, canceling a customer, and changing a user's service authority, and simultaneously accessing a broadband wireless access subsystem and a network subsystem. The parameter configuration, performance and security of the device are managed. Embodiment 4 FIG. 4 is a flowchart of a data transmission method of a TD-LTE-based broadband digital trunking system according to an embodiment of the present invention. The method is used for transmitting a cluster service, and may adopt the system of Embodiment 1 or 2 or the foregoing system. achieve. As shown in FIG. 4, the method mainly includes the following steps: Step S402: The cluster application server establishes an end-to-end session with the user terminal, and sends data from the user terminal to the LTE core network. Step S404: The LTE core network receives the data, allocates an IP multicast address to the session according to the group identifier of the target terminal group of the data, and sends the IP multicast address to the wireless access subsystem. Step S406: The evolved base station adds IP multicast corresponding to the IP multicast address according to the IP multicast address. Step S408: The LTE core network sends the data to an evolved base station that joins the IP multicast corresponding to the IP multicast address. Step S410: The evolved base station receives the data sent by the LTE core network, and sends the data to each target terminal in the target terminal group. The above method provided by the embodiment of the present invention can implement the transmission of the broadband cluster service through the existing LTE network, improve the utilization rate of the LTE network, and reduce the cost. In a preferred embodiment of the present invention, the P-GW of the LTE core network receives the data, and when determining that the received data is data of the cluster service, forwarding the data to the LTE core network. BM-SC, then, the BM-SC sends a session open request message to the MBMS-GW of the LTE core network, indicating that the MBMS service transmission is about to start; after the MBMS-GW receives the session open request message, it is a session for transmitting the MBMS service. An MBMS bearer context is created to save the session attribute, and a session open request message is sent to the MME of the LTE core network. After receiving the session open request message, the MME creates an MBMS bearer context for the session for transmitting the MBMS service, to save the session attribute. And sending a session open request to the MCE of the wireless access subsystem in the jurisdiction thereof, where the session open request carries the IP multicast address of the session. In another preferred embodiment of the present invention, after receiving the IP multicast address from the LTE core network, the MCE allocates a time-frequency resource for the session, establishes a service bearer, and provides one or more of its jurisdictions. The evolved base station sends a session open request message, and the one or more evolved base stations establish a radio resource for the MBMS service transmission, and configure the radio bearer transmitted by the MBSFN. In a preferred embodiment of the present invention, the IP multicast address may be allocated by the MBMS-GW. For example, the MBMS-GW may allocate the IP multicast address to the session according to the saved downlink data node list. And carrying the IP multicast address in the session open request message sent to the MME. Alternatively, in another preferred embodiment of the present invention, the IP multicast address may be allocated by the MME. For example, the MME may allocate the IP multicast address according to the evolved information to which each target terminal in the target terminal group belongs. . The MME may obtain, according to one of the following manners, the evolved information to which each target terminal belongs: (1) the MME obtains subscription information of each target terminal corresponding to the group identifier from the LTE core network HSS, according to The information about the evolved base station to which the target terminal belongs is determined by the subscription information obtained by the HSS; (2) the MME obtains information about the evolved base station to which each target terminal belongs from the subscription information reported by the cluster user terminal. . The fifth embodiment of the present invention uses the terminal A to call the terminal group B as an example to describe the cluster service transmission method of the TD-LTE based broadband digital trunking system provided by the embodiment of the present invention. In this embodiment, the terminal A and the terminal group B (including multiple terminals) may mainly include the following steps: Step 1. The terminal A is in an idle state, and the terminal group B (including multiple terminals) is in an idle state, and the terminal A is in the idle state. The group call is initiated to the terminal group B, and the terminal A and the eNodeB perform the interaction between the random access and the RRC connection establishment. Step 2: The UE initial message (including the service request) sent by the terminal A is transparently transmitted to the MME through the eNodeB, and the service request type is identified by the TMGI, and is represented as a group call request. Step 3: Terminal A interacts with the Serving Call Session Control Function (SCSCF) and the HSS to complete the security authentication of the terminal A and the IMS domain. Step 4: The terminal A interacts with the MME to complete the negotiation of the NAS security mechanism. Step 5: After receiving the UE initial message (including the service request) sent by the terminal A and transparently transmitted by the eNodeB, the MME completes the establishment of the initialization context by interacting with the eNodeB, and the eNodeB interacts with the terminal A to complete the establishment of the air interface radio resource. Step 6: The MME interacts with the S-GW, and the S-GW interacts with the P-GW to complete the update of the related bearer, where the P-GW saves the bearer as a group call request type. Step 7: The terminal A performs the SIP application layer signaling interaction with the Poc server to complete the establishment of the end-to-end SIP session. Step 8: The PoC server initiates a message of the right of the right to the terminal A, and simultaneously sends a message of the right of the right to the terminal group B, and then the terminal A sends the data to the PoC server. Step 9: After receiving the data of the terminal A, the PoC server sends data to the P-GW, and the P-GW determines that the bearer of the data is a group call request type, and considers that the multicast mode is sent, and then sends the data. To BM-SC. Step 10: After receiving the data, the BM-SC sends a Session Start Request message (Session Start Request message) 3\MBMS-GW, indicating that the MBMS transmission is about to start, and providing the session parameter to the MBMS-GW. The MBMS gateway sends a Session Start Response message to the BM-SC, and the MBMS-GW creates an MBMS Bearer Context to save the session attribute, and sends a session open request message to the MME, if it is a static multicast. In the Broadcast Single Frequency Network (MBSFN) area, the MBMS-GW allocates an IP multicast address to the session. If it is a dynamic MBSFN area, the MME allocates an IP multicast address to the session. The current protocol supports one TMGI corresponding to one MBMS service area, and one MBMS service area may have multiple TMGIs. For multiple different cluster services, it can be sent on the same MBMS service area. 1) For the static MBSFN area, the MBMS-GW stores TL information (ie, "List of downstream nodes"), that is, the eNB information included in the area. If the BM-SC learns from the P-GW that a certain cluster service starts, and then sends it to the MBMS-GW through the Session Start (the message carries the TMGI and the MBMS service area), the MBMS-GW sends the message to the MME through the Session Start (the message carries The TMGI/MBMS service area), along with TNL information (ie, "List of downstream nodes"), is carried to the MME, and the "TNL information" overwrites the "TNL information" generated by the MME itself.

2) For the dynamic MBSFN area, the MBMS-GW does not store TNL information (ie, "List of downstream nodes"), that is, the eNB information contained in the area. If the BM-SC knows a cluster service start (TMGI) from the PDN GW, and then sends it to the MBMS GW through the Session Start (the message carries the TMGI and the MBMS service area), the MBMS GW sends the message to the MME through the Session Start (the message carries The TMGI/MBMS service area) does not carry the information to the MME because the MBMS GW does not have TNL information. The MME automatically generates the TNL information according to the eNB information to which the cluster terminal belongs. Step 11: After receiving the session open request, the MME creates an MBMS bearer context to save the session attribute, and sends a session open request to the MCE in its own jurisdiction. Contains an IP multicast address. Step 12: After receiving the session open request, the MCE establishes a service bearer if the radio resource is sufficient, and responds to the session start response message to the MME, and simultaneously sends a session open request message to the eNodeB under the jurisdiction of the MCE. Step 13: The eNodeB in the MCE jurisdiction receives the session start request message, prepares to receive the MBMS service, and responds to the MCE response session start response message, and joins the IP multicast corresponding to the service. Step 14: The eNodeB establishes a radio resource for the MBMS data transmission, and completes the radio bearer configuration of the MBSFN transmission. Step 15. The BM-SC starts transmitting data to the MBMS-GW. Step 16. The MBMS-GW sends the data to the eNodeB that has joined the IP multicast. Step 17. The eNodeB sends the data to all terminals in the terminal group B at a specified time. From the above description, it can be seen that, in the embodiment of the present invention, the cluster application server is combined with the LTE system to implement the cluster service, and the current existing LTE network can be implemented without adding a new network element device. The broadband digital trunking service reduces the cost and improves the utilization of the LTE network. It will be apparent to those skilled in the art that the various modules or steps of the present invention described above can be implemented by a general-purpose computing device that can be centralized on a single computing device or distributed across multiple computing devices. Alternatively, they may be implemented by program code executable by the computing device, such that they may be stored in the storage device by the computing device and, in some cases, may be different from this The steps shown or described are performed sequentially, or they are separately fabricated into individual integrated circuit modules, or a plurality of modules or steps thereof are fabricated as a single integrated circuit module. Thus, the invention is not limited to any specific combination of hardware and software. The above is only the preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes can be made to the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and scope of the present invention are intended to be included within the scope of the present invention.

Claims

1. A broadband digital trunking system based on time-division long-term evolution TD-LTE, including:

One or more cluster application servers, configured to schedule cluster services, schedule and manage end-to-end sessions of user terminals, and send data from the user terminals to a long-term evolution LTE core network; the LTE core network is set to receive Transmitting, by the group identifier of the target terminal group of the data, an Internet Protocol IP multicast address for the session, and transmitting the IP multicast address to a wireless access subsystem, and then sending the data An evolved base station that joins the IP multicast corresponding to the IP multicast address;

The radio access subsystem includes: one or more evolved base stations, configured to add an IP multicast corresponding to the IP multicast address according to the IP multicast address, and receive the location sent by the LTE core network Describe the data and send the data to each target terminal in the target terminal group.

2. The system according to claim 1, wherein the wireless access subsystem further comprises: a primary communication device MCE; the LTE core network comprises: a packet data network gateway P-GW, and a broadcast multicast service center BM- The SC, the multimedia broadcast multicast service gateway MBMS-GW, and the mobility management entity MME; wherein the P-GW is configured to receive the data, and when determining that the received data is the data of the cluster service in the multicast mode, Transmitting the data to the BM-SC;

The BM-SC is configured to send a session open request message to the MBMS-GW, indicating that the MBMS service transmission is about to start;

The MBMS-GW is configured to create an MBMS bearer context for the session, and send a session open request message to the MME;

The MME is configured to receive the session open request message, create an MBMS bearer context for the session, and send a session open request to the MCE in its jurisdiction, where the session open request carries the session IP multicast address;

The MCE is configured to allocate a time-frequency resource for the session, establish a service bearer, and send a session open request message to the one or more evolved base stations in its jurisdiction;

The one or more evolved base stations are configured to establish a radio resource for the MBMS service transmission, and configure a radio bearer transmitted by the multicast broadcast single frequency network MBSFN. The system according to claim 2, wherein said MBMS-GW is further configured to allocate said IP multicast address to said session according to a list of downlink data stream nodes it holds, and carry said IP multicast address In the session open request message sent to the MME. The system according to claim 2, wherein the MME is further configured to allocate the IP multicast address according to evolved information to which each target terminal in the target terminal group belongs. The system according to claim 4, wherein

The LTE core network further includes: a home subscriber server HSS, configured to store subscription information of the cluster user terminal;

The MME is further configured to: obtain subscription information of each target terminal corresponding to the group identifier from the HSS, and determine, according to the subscription information acquired from the HSS, an evolved base station to which each target terminal belongs Information. The system according to claim 4, wherein the MME is further configured to acquire information of an evolved base station to which each of the target terminals belongs from the subscription information reported by the cluster user terminal. The system according to any one of claims 1 to 6, wherein the system further comprises:

An IP Multimedia Subsystem IMS, configured to forward data between the one or more cluster application servers and the LTE core network. The system according to any one of claims 1 to 6, wherein the system further comprises: an operation and maintenance subsystem, configured to manage the cluster user terminal, and configure the wireless access subsystem and the LTE The parameters of the device in the core network. The system according to any one of claims 1 to 6, wherein the one or more cluster application servers comprise: a push-to-talk over PoC-based application server, an application server based on a global open cluster structure Gota. A data transmission method for a broadband digital trunking system based on time-division long-term evolution TD-LTE, comprising: after an end-to-end session establishment of a user terminal, the cluster application server sends data from the user terminal to a long-term evolution LTE core network ;

Receiving, by the LTE core network, the data, assigning an Internet Protocol IP multicast address to the session according to the group identifier of the target terminal group of the data, and transmitting the IP multicast address to the wireless access subsystem Evolved base station; The evolved base station adds an IP multicast corresponding to the IP multicast address according to the IP multicast address;

Sending, by the LTE core network, the data to an evolved base station that joins the IP multicast corresponding to the IP multicast address;

The evolved base station receives the data sent by the LTE core network, and sends the data to each target terminal in the target terminal group.

11. The method according to claim 10, wherein the LTE core network receives the data, allocates an IP multicast address to a session according to a group identifier of a target terminal group of the data, and multicasts the IP The address is sent to the wireless access subsystem, including:

The packet data network gateway P-GW of the LTE core network receives the data, and when determining that the received data is data of a cluster service, forwarding the data to a broadcast multicast service center BM of the LTE core network. SC;

Sending, by the BM-SC, a session open request message to the multimedia broadcast multicast service gateway MBMS-GW of the LTE core network, indicating that the MBMS service transmission is about to start;

The MBMS-GW creates an MBMS bearer context for the session for transmitting the MBMS service, and sends a session open request message to the MME of the LTE core network;

Receiving, by the mobility management entity MME, the session open request message, creating an MBMS bearer context for the session for transmitting the MBMS service, and sending a session to a primary communication device MCE of the wireless access subsystem within its jurisdiction The request is opened, where the session open request carries the IP multicast address of the session.

12. The method according to claim 11, wherein

The MCE allocates a time-frequency resource for the session, establishes a service bearer, and sends a session open request message to the one or more evolved base stations in its jurisdiction; the one or more evolved base stations are The MBMS service transmission establishes radio resources and configures the radio bearers transmitted by the MBSFN.

The method according to claim 11, wherein, before the MBMS-GW sends a session open request message to the MME, the method further includes: the MBMS-GW according to the saved downlink data flow node list, Allocating the IP multicast address to the session, and carrying the IP multicast address in the session open request message sent to the MME.

The method according to claim 11, wherein, before the MME sends a session open request to an MCE of the radio access subsystem in its jurisdiction, the method further includes: the MME according to the target The evolved information to which each target terminal belongs in the terminal group allocates the IP multicast address.

The method according to claim 14, wherein the MME obtains the evolved information to which each target terminal belongs in the following manner:

And obtaining, by the MME, the subscription information of each target terminal corresponding to the group identifier from the LTE core network HSS, and determining, according to the subscription information acquired by the HSS, an evolved base station to which each target terminal belongs Information; or,

And obtaining, by the MME, the information of the evolved base station to which each target terminal belongs from the subscription information reported by the cluster user terminal.