"Call Control (CC)

## 定义 / Definition

### English Protocol functions for establishing, maintaining, modifying, and releasing voice/data calls between mobile stations and network. CC is responsible for the call setup, call progression, and call teardown procedures.

### 中文 用于在移动台和网络之间建立、维护、修改和释放语音/数据呼叫的协议功能。CC负责呼叫建立、呼叫进行和呼叫拆除流程。

## 呼叫状态机 / Call State Machine

IDLE -> CALL_PENDING -> ACTIVE -> RELEASED

## CC 流程 / CC Procedures

### 英文

流程英文描述 ------------------ 呼叫建立Call SetupEstablish call connection 呼叫进行Call ProgressionHandle call progress 呼叫释放Call ReleaseTeardown call connection 呼叫修改Call ModificationChange call parameters

### 中文

流程描述 ------------ MO Call移动台发起的呼叫 MT Call移动台接收的呼叫 Emergency Call紧急呼叫

## 消息示例 / Message Examples

消息方向描述 ------------------ SETUPMS → Network呼叫建立请求 CALL_PROCEEDINGNetwork → MS呼叫正在处理 ALERTINGNetwork → MS被叫振铃 CONNECTNetwork → MS呼叫连接 CONNECT_ACKMS → Network连接确认

## 交叉引用 / Cross References

- TS 24.007 - 信令层3总体方面 - TS 24.008 - CC procedures - TS 24.301 - EPS call control - Layer 3 (L3) - 服务原语