WO2012051857A1

WO2012051857A1 - Method, user equipment and system for point-to-point call in trunking system

Info

Publication number: WO2012051857A1
Application number: PCT/CN2011/075107
Authority: WO
Inventors: 杜高鹏; 朱永升; 韩小江; 张鹏帅
Original assignee: 中兴通讯股份有限公司
Priority date: 2010-10-20
Filing date: 2011-06-01
Publication date: 2012-04-26
Also published as: CN102457813A

Abstract

A method, a User Equipment (UE) and a system for point-to-point call in a trunking system based on the Long Term Evolution (LTE) technology. According to the method, terminal and system of the present invention, a source UE establishes a conversation channel with a target UE through an eNode B, a core network, an Internet Protocol Multimedia Subsystem (IMS) domain and an application server, and transfers voice data with the target UE through the conversation channel. The present invention implements the point-to-point trunking communication mechanism through function extension based on the existing air interface protocol, adopts the IMS plus Push-To-Talk over cellular (PoC) architecture, and performs function extension on part network elements in the existing network architecture. Specifically, with the present invention, the conversation channel between the source UE and the target UE is established through the Node B, the core network, the IMS domain and the application server; voice data is transferred with the target UE through the conversation channel; and thereby the point-to-point service in the trunking system is realized in the LTE network, which is more advantageous to the compatibility and convergence between the trunking system and the existing LTE network.

Description

Point-to-point calling method, terminal and system in cluster system

The present invention relates to the field of communications technologies, and in particular, to a point-to-point calling method, terminal, and system in a cluster system based on LTE (Long Term Evolution) technology. Background technique

At present, the trunking communication system is a dedicated wireless communication system developed for industrial users to command and dispatch requirements. It is a multi-purpose wireless communication system in which a large number of wireless users share a small number of wireless channels and use command and dispatch as the main application. High performance wireless communication system. The trunking communication system has a wide application market in the fields of government departments, public safety, emergency telecommunications, electric power, civil aviation, petrochemicals and military.

The trunked communication system has undergone a similar development process as cellular mobile communication systems. The first generation cluster system is an analog trunking communication system, which mainly supports voice communication; the second generation cluster system is a narrowband digital trunking communication system, which is the most widely used cluster communication system.

The existing trunking communication system is still relatively backward in terms of data transmission capability and multimedia service support capability, and its technical innovation and industrial chain are still not complete. For example, in the current digital narrowband trunking communication system, the iDEN system improves the time slot and modulation method and introduces a broadband integrated digital enhanced network (Wide-iDEN, WiDEN), which increases the peak transmission rate to 384 kbps; TETRA enhanced data. The TETRA Release 2 Enhanced Data Service (TEDS) can ideally support peak transmission rates of up to 700 kbps, which are not on the order of Mbps. In addition, existing digital trunking systems are not well suited to demand in terms of spectrum utilization and coverage.

At present, the broadband digital trunking system based on LTE technology has become the development direction of the next-generation cluster system, and the network architecture and business process of the broadband digital trunking system based on LTE technology. Standards such as business functions and key technologies have not yet been developed, while existing second-generation cluster systems are based

The evolution of broadband digital trunking systems based on LTE technology has great difficulties, and it does not have compatibility or compatibility with LTE networks. Summary of the invention

The main purpose of the present invention is to provide a point-to-point calling method, terminal and system in a cluster system based on LTE technology, aiming at improving the compatibility of a trunking call service with an LTE network.

In order to achieve the above object, the technical solution of the present invention is achieved as follows:

A point-to-point calling method in a cluster system, the method comprising:

The source terminal establishes a communication channel with the destination terminal through the base station, the core network, the IP multimedia subsystem IMS domain, and the application server;

The voice data is transmitted to the destination terminal through the call channel.

The process of establishing a call channel between the source terminal and the destination terminal by using the base station, the core network, the IMS domain, and the application server includes:

The source terminal establishes an RRC connection by sending a radio resource control protocol RRC connection request to the base station;

Sending a service request carrying a point-to-point cluster call identifier to the base station, and the base station forwards the service request to the core network, and performs security authentication of the IMS domain at the same time;

Establishing a radio bearer with the base station, and updating the bearer information by using the mobility management entity MME, the serving gateway SGW, and the public data network gateway PDN-GW in the core network;

Sending a session establishment request message to the application server, and receiving a call permission message fed back by the application server according to the session establishment request message, establishing a communication channel with the destination terminal.

The process of transmitting voice data through the call channel and the destination terminal includes:

The source terminal sends voice data to the application server through the call channel, and the application server forwards the voice data to the core network; When the core network determines that the bearer in which the voice data is located is a point-to-point type, the voice data is forwarded by the core network to the base station, and then the base station forwards the voice data to the destination terminal.

A point-to-point calling terminal in a cluster system, the terminal comprising:

A call channel establishing module is configured to establish a call channel between the base station, the core network, the IMS domain, and the application server.

The call channel establishing module includes:

An RRC connection establishing unit, configured to establish an RRC connection by sending an RRC connection request to the base station;

a service request sending unit, configured to send a service request carrying a point-to-point cluster call identifier to the base station, trigger the base station to forward the service request to the core network, and perform security authentication of the IMS domain at the same time; and the radio bearer establishes an update unit, configured to establish a base station Inter-radio bearer, and update bearer information through the MME, SGW, and PDN-GW in the core network;

The session request message sending unit is configured to send a session establishment request message to the application server, and the call channel establishing unit is configured to receive a call permission message fed back by the application server according to the session establishment request message, and establish a call channel with the destination terminal.

The call initiation module is further configured to:

Transmitting voice data to the application server through the call channel, and forwarding, by the application server, the voice data to a core network;

When the trigger core network determines that the bearer of the voice data is a point-to-point type, the voice data is forwarded to the base station, and the base station is triggered to forward the voice data to the destination terminal.

A point-to-point calling system in a cluster system, the system comprising: a source terminal and a destination terminal capable of communicating with a base station, and an application server connected to the base station through a core network, wherein:

The source terminal is configured to be established by using a base station, a core network, an IMS domain, and an application server. a call channel between the destination terminals; and the voice data is transmitted to the destination terminal through the call channel;

The application server is configured to establish, by the base station, the core network, and the IMS domain, a call channel between the source terminal and the destination terminal, so that the source terminal performs voice data transmission between the call channel and the destination terminal;

The destination terminal is configured to perform voice data transmission with the source terminal by using the call channel.

The source terminal is further configured to:

Establishing an RRC connection by sending an RRC connection request to the base station; transmitting a service request carrying the point-to-point cluster call identifier to the base station, triggering the base station to forward the service request to the core network, and performing security authentication of the IMS domain; and establishing a relationship with the base station Radio bearer, and performing update of bearer information by using the MME, the SGW, and the PDN-GW in the core network; sending a session establishment request message to the application server, and receiving a call permission message fed back by the application server according to the session establishment request message, a communication channel with the destination terminal;

The application server is further configured to receive a session establishment request message sent by the source terminal, and feed back a call permission message to the source terminal according to the session establishment request message.

among them,

The source terminal is further configured to send voice data to the application server by using the call channel;

The application server is further configured to forward the received voice data to the core network, and the triggering core network forwards the voice data to the base station when determining that the bearer of the voice data is a point-to-point type, and triggering the base station to The voice data is forwarded to the destination terminal.

The application server is a cluster push application server based on a push-to-talk over PoC. The invention provides a point-to-point calling method, terminal and system in a cluster system based on LTE technology, and performs work on the basis of the existing air interface protocol and tries not to change or try to be as small as possible. It can be expanded to complete the peer-to-peer cluster communication mechanism, using IMS (IP Multimedia Subsystem, IP Multimedia Subsystem) + PoC (PTT Over Cellular) architecture, and functioning for some network elements in the existing network architecture. Expanding, specifically establishing a call channel between the source terminal and the destination terminal through the base station, the core network, the IMS domain, and the application server; performing voice data transmission with the destination terminal through the call channel, and implementing point-to-point service of the cluster system in the LTE network, It also makes use of the compatibility and integration of the cluster system with the existing LTE network. DRAWINGS

1 is a schematic flowchart of an embodiment of a point-to-point calling method in a trunking system based on the LTE technology of the present invention;

2 is a schematic diagram of a network structure of a broadband digital trunking communication system based on the LTE technology in the foregoing embodiment;

3 is a schematic diagram of a process of establishing a call channel between a source terminal and a destination terminal through a base station, a core network, an IMS domain, and an application server according to an embodiment of the LTE technology-based point-to-point call method in a cluster system;

4 is a schematic structural diagram of an embodiment of a point-to-point calling terminal in a cluster system based on the LTE technology of the present invention;

5 is a schematic structural diagram of a call channel establishment module in an embodiment of a point-to-point calling terminal in a cluster system according to the present invention;

6 is a schematic structural diagram of an embodiment of a point-to-point calling system in a trunking system based on the LTE technology of the present invention. detailed description

The solution of the embodiment of the present invention mainly completes the point-to-point cluster communication mechanism based on the existing air interface protocol and does not change or minimize the function expansion, adopts the IMS+PoC architecture, and uses the existing network. Some network elements in the architecture are functionally expanded, specifically The station, the core network, the IMS domain, and the application server establish a call channel between the source terminal and the destination terminal. The voice data is transmitted through the call channel and the destination terminal to implement the point-to-point service of the cluster system in the LTE network.

As shown in FIG. 1 , an embodiment of the present invention provides a point-to-point calling method in a cluster system based on LTE technology, including:

Step S101: The source terminal establishes a call channel with the destination terminal by using the base station, the core network, the IMS domain, and the application server.

The method in this embodiment involves a trunking system call service based on an LTE network. When a cluster terminal (that is, the source terminal in this embodiment) in the cluster system initiates a call to another cluster terminal in the cluster system (that is, the destination terminal in this embodiment) When you first need to establish a call channel between the source terminal and the destination terminal.

As shown in FIG. 2, the network structure of the broadband digital trunking communication system based on the LTE technology includes: a terminal (UE, User Equipment, user), a network side, and an application side, where:

The application side, which includes the cluster application server, completes the scheduling function of the cluster service and is the entry point of the PDN gateway. The cluster application servers include cluster application servers such as PoC-based cluster applications, cluster application servers based on Gota (Global Open Trusilization Architecture), and other types of cluster application servers. For the PoC-based cluster application server, when the end-to-end cluster call service is completed, the application side also includes the IMS domain.

CSCF (Call Session Control Function) is a functional entity inside IMS. It is the core of the entire IMS network and is mainly responsible for handling signaling control during multimedia call sessions. It manages user authentication of the IMS network, QoS of the IMS bearer plane, control of SIP sessions with other network entities, and service negotiation and resource allocation.

The CSCF is divided into a proxy CSCF (P-CSCF, Proxy CSCF), a query CSCF (I-CSCF, Interrogating CSCF), and a service CSCF (S-CSCF, Serving CSCF) according to functions, which are essentially SIP servers for processing SIP messages. make. among them: The P-CSCF is the unified entry point for the IMS visited network. All session messages initiated and terminated by the IMS terminal to the IMS terminal are passed through the P-CSCF. As a SIP Proxy, the P-CSCF is responsible for user authentication and IPSec management independent of the access network, network anti-attack and security protection, SIP signaling compression and decompression for saving wireless network resources, and user roaming control through PDF ( Policy Decision Function) Performs functions such as NAT and QoS on the bearer plane. Its main functions are: forwarding the SIP registration request sent by the UE to the I-CSCF, determining the I-CSCF by the domain name provided by the UE; forwarding the SIP message sent by the UE to the S-CSCF, when the P-CSCF initiates the registration process at the UE Determine the S-CSCF.

The I-CSCF is the entry point to the IMS home network. During the registration process, the I-CSCF selects an S-CSCF for the user by querying the HSS. During the call, the call to the IMS network is first routed to the I-CSCF, and the I-CSCF obtains the S-SCSCF address registered by the user from the HSS and routes the message to the S-CSCF. Its main functions are: Specifying an S-CSCF for the user to perform SIP registration; Obtaining the address of the S-CSCF from the HSS, forwarding the SIP request; Routing the SIP request from other networks to the S-CSCF.

The S-CSCF is at the core of IMS network session control. It accepts registration requests forwarded from the visited network through the P-CSCF and cooperates with the HSS for user authentication. The service data signed by the user is downloaded from the HSS. The S-CSCF performs routing management on the calling and called sides of the user, and performs SIP AS triggering based on the initial filtering rules (iFC, Initial Filter Criteria) of the user subscription to implement rich IMS service functions. Its main functions are: After receiving the registration request, the registration request is validated by the HSS; and the registered session terminal is controlled as the Proxy-Server. After receiving the request, it can perform internal processing or forwarding. It can also be used as a UA to interrupt or initiate SIP transactions. It interacts with the service platform to provide multimedia services.

On the network side, on the basis of supporting existing functions, the cluster service function is added, that is, the cluster user subscription information and the cluster network service network group call are stored and managed. The network side includes a base station and a core network, where the core network involves a PDN gateway, MME (Mobility Management Entity, mobile Sexual management entities) and HSS.

PDN (Public Data Network) Gateway (PDN-GW), which supports existing functions and supports interfaces with a variety of cluster application servers to support various cluster services according to different needs. For the cluster service, the PDN-GW can select whether the downlink data is distributed to the SGW (Seving GateWay, Service Gateway) or the BM-SC according to whether the single call (ordinary bearer) or the group call (each cluster service group is assigned a TMGI identifier). That is, whether unicast mode or multicast mode (MBSFN mode) is selected.

The HSS (Home Subscriber Server) supports existing functions and adds cluster-capable modules for storing and managing group user information related to cluster services.

The MME supports the existing functions and adds modules that support the cluster function. The new module supports cluster services, stores information about the cluster user terminals, and is responsible for obtaining the subscription information of the cluster user terminals from the HSS. The MME is a key control node of the 3GPP protocol LTE access network, which is responsible for the positioning of the UE in the idle mode, and the paging process, including the relay. It involves the bearer activation/shutdown process. And when a UE is initialized, the UE is selected to connect to an SGW. A user is authenticated by interacting with the HSS, and a temporary ID is assigned to a user. MME also supports interception and monitoring within the scope permitted by law. The MME provides a control function interface for the 2G/3G access network. The S3 interface also provides the S6a interface for the roaming UE to the HSS.

Both the SGW and the eNB support existing functions in accordance with the LTE standard.

In this embodiment, a cluster application server is used as a PoC-based cluster application server as an example.

In this embodiment, the source terminal in the cluster system establishes a call channel with the destination terminal through the base station, the core network, the IMS domain, and the application server, and the specific process is:

For the source terminal and the destination terminal in the cluster system, both of them are in an idle state, and when the source terminal initiates a call service to the destination terminal, the source terminal and the base station first establish a radio bearer, and then proceed. Random access and RRC (Radio Resource Control) connection establishment. The problem of bearer, that is, bearing load and radio bearer selection, is actually the question of which wireless data service to choose as the data path.

The RRC processes the third layer information of the control plane between the UE and the UTRAN. The RRC mainly includes the RRC CONNECTION MANAGEMENT PROCEDURES, the RADIO BEARER CONTROL PROCEDURES, the RRC CONNECTION MOBILITYPROCEDURES, and the MEASUREMENT PROCEDURES.

The RRC connection setup procedure includes reselection of available cells, access grant control, and establishment of Layer 2 signal links. The RRC connection release is requested by the upper layer for tearing down the last signal connection; or when the RRC link fails, it is initiated by the RRC layer. If the connection fails, the UE will request to re-establish the RRC connection. If the RRC connection fails, the RRC releases the allocated resources.

After the RRC is established, the source terminal sends an initial UE message to the core network through the base station, and interacts with the SCSCF and the HSS in the IMS domain to complete the security authentication of the source terminal and the IMS domain. The initial UE message includes a service request, and the service request type identifier For point-to-point cluster calls.

After the security authentication of the IMS domain is completed, the NAS security mechanism between the source terminal and the MME in the core network is negotiated. MME performs initial context setup procedure, to produce EPS bearer context in the eNB and the terminal, and for establishing a wireless air interface resources that is RB (radio bearer, wireless carrier ⁷⁾ established.

The MME updates the relevant bearer for the serving gateway and the PDN-GW, where the information includes a point-to-point bearer type, so that the PDN-GW uses the information to distinguish the data flow direction in subsequent processes.

Then, after the source terminal and the Poc server perform SIP application layer signaling interaction, an end-to-end SIP session is established. At this time, the PoC server initiates a message of the right to grant permission to the source terminal, and simultaneously sends a message of the right to the destination terminal to the destination terminal. , then you can make a voice call service, complete A call channel is established between the source terminal and the destination terminal.

After receiving the voice data of the source terminal, the PoC server sends the voice data to the PDN-GW. The PDN-GW determines that the bearer of the voice data is a point-to-point type, and then sends the data to the SGW, and then performs voice according to a normal process. The transmission of data.

Step S102, the voice data is transmitted through the call channel and the destination terminal.

As described above, the source terminal sends the voice data to the application server through the call channel, and the application server forwards the voice data to the core network. When the core network determines that the bearer of the voice data is a point-to-point type, the voice data is used by the core network. Forwarded to the base station, and then the base station forwards the voice data to the destination terminal.

Similarly, after receiving the paging message forwarded by the MME by the MME, the destination terminal initiates a random access and RRC connection establishment procedure, and the call flow is the same as the source terminal initiates the call flow.

As shown in FIG. 3, step S101 includes:

Step S1011: The source terminal requests to establish an RRC connection by sending an RRC connection to the base station. Step S1012: Send a service request carrying a point-to-point cluster call identifier to the base station, and the base station forwards the service request to the core network, and simultaneously performs security of the IMS domain. Certification

Step S1013: Establish a radio bearer with the base station, and perform update of the bearer information by using the MME, the SGW, and the PDN-GW in the core network.

After the source terminal establishes a radio bearer with the base station, the MME sends the update bearer request information to the SGW in the core network, where the update bearer request information carries the point-to-point cluster call identifier, and the SGW forwards the update bearer request information to the PDN. The GW, the PDN-GW can determine that the call is a single call (common bearer) according to the received update bearer request information, and the PDN-GW selects to distribute the downlink data to the SGW according to the single call, that is, selects the unicast mode.

Step S1014: Send a session establishment request message to the application server.

Step S1015: Receive a call permission message fed back by the application server according to the session establishment request message, and establish a call channel with the destination terminal. As can be seen from the above process, for the point-to-point call service in the cluster system, the existing network architecture and message flow of the LTE network are used, and the IMS+PoC architecture is used to implement the compatibility of the cluster call with the existing LTE network.

In this embodiment, the point-to-point cluster communication mechanism is completed by performing function expansion on the basis of the existing air interface protocol and as far as possible or as small as possible, using the IMS+PoC architecture, and part of the network in the existing network architecture. The function is extended by the element, and the call channel between the source terminal and the destination terminal is established through the base station, the core network, the IMS domain, and the application server; the voice data is transmitted through the call channel and the destination terminal, and the point-to-point service of the cluster system in the LTE network is realized. The use of cluster systems and existing LTE networks is more integrated.

As shown in FIG. 4, an embodiment of the present invention provides a point-to-point calling terminal in a cluster system based on the LTE technology, including: a call channel establishing module 401 and a call initiating module 402, wherein: a call channel establishing module 401 is configured to pass the base station. a core network, an IMS domain, and an application server establish a call channel with the destination terminal;

The method in this embodiment involves a cluster system call service based on an LTE network. When a cluster terminal (that is, a terminal in this embodiment) in the cluster system initiates a call to another cluster terminal in the cluster system (that is, the destination terminal in this embodiment) First, the call channel establishing module 401 first establishes a call channel between the terminal and the destination terminal.

The call initiation module 402 is configured to transmit voice data through the call channel and the destination terminal.

In this embodiment, the specific process in which the terminal in the cluster system establishes a call channel with the destination terminal through the base station, the core network, the IMS domain, and the application server, and transmits the voice data through the call channel and the destination terminal is:

The terminal and the destination terminal are both in an idle state. When the terminal initiates a call service to the destination terminal, the terminal and the base station first establish a radio bearer, and then perform random access and perform RRC connection establishment. After the RRC is established, the terminal sends an initial UE message to the core network through the base station, and interacts with the SCSCF and the HSS in the IMS domain to complete the security authentication of the terminal and the IMS domain. The initial UE message includes a service request, and the service request type identifier is point-to-point. Cluster call.

After the security authentication of the IMS domain is completed, the NAS security mechanism between the terminal and the MME in the core network is negotiated. The MME performs an initialization context establishment process, generates an EPS bearer and a terminal context in the eNB, and performs RB establishment on the air interface to establish the radio resource.

Then, after the terminal performs the SIP application layer signaling interaction with the Poc server, an end-to-end SIP session is established. At this time, the PoC server initiates a message for the right of the right to the terminal, and simultaneously sends a message for the right of the call to the destination terminal, and then The voice call service can be performed, and the call channel establishment between the terminal and the destination terminal is completed.

After receiving the voice data of the terminal, the PoC server sends voice data to the PDN-GW. The PDN-GW determines that the bearer of the voice data is a point-to-point type, and then sends the data to the SGW, and then performs voice data according to a normal process. Send.

As shown in FIG. 5, the call channel establishing module 401 includes: an RRC connection establishing unit 4011, a service request sending unit 4012, a radio bearer setup updating unit 4013, a session request message sending unit 4014, and a call channel establishing unit 4015, where:

The RRC connection establishing unit 4011 is configured to establish an RRC connection by sending an RRC connection request to the base station.

The service request sending unit 4012 is configured to send, to the base station, a service request that carries the point-to-point cluster call identifier, and the base station forwards the service request to the core network, and performs security authentication of the IMS domain at the same time;

The radio bearer establishment update unit 4013 is configured to establish a radio bearer with the base station, and perform update of the bearer information by using the MME, the SGW, and the PDN-GW in the core network; a session request message sending unit 4014, configured to send a session establishment request message to the application server;

The call channel establishing unit 4015 is configured to receive a call permission message fed back by the application server according to the session establishment request message, and establish a call channel with the destination terminal.

Further, the call initiation module 402 is further configured to send voice data to the application server through the call channel, and the application server forwards the voice data to the core network. When the core network determines that the bearer of the voice data is a point-to-point type, the voice is sent by the core network. The data is forwarded to the base station, and the base station forwards the voice data to the destination terminal.

As shown in FIG. 6, an embodiment of the present invention provides a point-to-point calling system in a cluster system based on the LTE technology, including: a source terminal 602 and a destination terminal 603 respectively connected to the base station 601, and an application connected to the base station 601 through the core network. Server 604, where:

The source terminal 602 is configured to establish a call channel with the destination terminal 603 through the base station 601, the core network, the IMS domain, and the application server 604. The voice data is transmitted through the call channel and the destination terminal 603.

The application server 604 is configured to establish a call channel between the source terminal 602 and the destination terminal 603 for the source terminal 602 through the base station 601 core network and the IMS domain, so that the source terminal 602 can transmit the voice data between the call channel and the destination terminal 603.

The destination terminal 603 is configured to receive voice data sent by the source terminal 602 through the call channel. Further, the source terminal 602 is further configured to: establish an RRC connection by sending an RRC connection request to the base station 601; send a service request carrying the point-to-point cluster call identifier to the base station 601, and the base station 601 forwards the service request to the core network, and simultaneously performs IMS Security authentication of the domain; establishing a radio bearer with the base station 601, and performing update of the bearer information through the MME, the SGW, and the PDN-GW in the core network; transmitting a session establishment request message to the application server 604; and receiving the application server 604 according to the session establishment Requesting a call permission message fed back by the message, establishing a call channel with the destination terminal 603; The application server 604 is further configured to receive the session establishment request message sent by the source terminal 602, and feed back the call permission message to the source terminal 602 according to the session establishment request message.

Further, the source terminal 602 is further configured to send voice data to the application server 604 through the call channel;

The application server 604 is further configured to forward the voice data to the core network. When the core network determines that the bearer of the voice data is a point-to-point type, the core network forwards the voice data to the base station 601, and then the base station 601 forwards the voice data to the Destination terminal 603.

In this embodiment, the application server 604 is a PoC-based cluster application server. Similarly, the application server 604 in this embodiment may also be a Gota-based cluster application server and other types of cluster application servers, when using a Gota-based cluster application server and other types of cluster application servers, due to a Gota-based cluster application. The server contains IMS functionality and does not need to go through the IMS domain.

The point-to-point calling method, terminal and system in the cluster system based on the LTE technology in the embodiment of the present invention complete the point-to-point cluster communication mechanism by performing function expansion on the basis of the existing air interface protocol and not changing as much as possible or as small as possible. The IMS+PoC architecture is used to extend the function of some network elements in the existing network architecture, and the call channel between the source terminal and the destination terminal is established through the base station, the core network, the IMS domain, and the application server. The terminal performs voice data transmission, realizes the point-to-point service of the cluster system in the LTE network, and more utilizes the compatibility and fusion of the cluster system and the existing LTE network.

The above is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention, and equivalent structural or process changes made by the present specification and drawings may be directly or indirectly applied to other related technical fields. The same is included in the scope of patent protection of the present invention.

Claims

Claim

A point-to-point calling method in a cluster system, the method comprising:

The method according to claim 1, wherein the process of establishing a call channel between the source terminal and the destination terminal by using the base station, the core network, the IMS domain, and the application server includes:

The method according to claim 1 or 2, wherein the process of transmitting voice data through the call channel and the destination terminal comprises:

The source terminal sends voice data to the application server through the call channel, and the application server forwards the voice data to the core network;

When the core network determines that the bearer in which the voice data is located is a point-to-point type, the voice data is forwarded by the core network to the base station, and then the base station forwards the voice data to the destination terminal.

4. A point-to-point calling terminal in a cluster system, the terminal comprising:

a call channel establishing module, configured to establish a call channel with the destination terminal through the base station, the core network, the IMS domain, and the application server; Pass.

The terminal according to claim 4, wherein the call channel establishing module comprises: an RRC connection establishing unit, configured to establish an RRC connection by sending an RRC connection request to the base station;

The terminal according to claim 4 or 5, wherein the call initiation module is further configured to: send voice data to the application server by using the call channel, and forward, by the application server, the voice data to a core network ;

The source terminal is configured to establish a call channel with the destination terminal by using the base station, the core network, the IMS domain, and the application server, and transmit the voice data to the destination terminal by using the call channel;

The destination terminal is configured to perform voice data with the source terminal by using the call channel. Pass.

The system according to claim 7, wherein the source terminal is further configured to: establish an RRC connection by sending an RRC connection request to the base station; and send a service request carrying the point-to-point cluster call identifier to the base station, triggering the base station to The service request is forwarded to the core network, and the IMS domain is authenticated at the same time; and the radio bearer is established with the base station, and the bearer information is updated by the MME, the SGW, and the PDN-GW in the core network; and the session is also sent to the application server. Establishing a request message, and receiving a call permission message fed back by the application server according to the session establishment request message, establishing a call channel with the destination terminal;

9. The system according to claim 7 or 8, wherein

10. The system according to claim 9, wherein the application server is a push-to-talk over PoC-based cluster application server.