自动控制文献翻译——6 功能需求

CBTC系统应包括ATP、ATO和ATS功能。ATP功能为防止碰撞、超速和其他危险情况，提供了故障—安全防护。ATP功能应优先于ATO和ATS功能。ATO功能可以控制本该由列车司机执行的基本操作，并且在ATP的限速保护之下进行控制。ATS功能可以提供系统的状态信息并且能对系统的各种功能提供监控和取消自动控制的方法。

CBTC车地通信接口应能充分的支持所有所需的ATP、ATO和ATS功能。数据链路在CBTC区域内提供连续的地理覆盖，并且能支持列车在隧道、管道、接口处、高层轨道和水平面轨道的运行。数据链路能支持双向的数据传输并且具有足够低的延时性来支持特定的性能需求。数据链路应包括协议结构来支持列车控制信息安全、及时、可靠的传递。

6.1 ATP功能

所有的ATP功能都是关键功能，根据5.3来进行设计和执行。

CBTC系统有能力提供双向的ATP。

6.1.1列车定位/列车速度决策

6.1.1.1 CBTC列车定位/列车速度决策

CBTC的列车定位/列车速度决策对于CBTC系统结构来说是一个必须的ATP功能。

CBTC系统能为每个在CBTC区域中运行的、具有CBTC设备的列车建立定位、速度和运行方向信息。

CBTC列车定位决策能对列车的车头和车尾进行安全、准确的定位。CBTC列车定位决策功能可以充分地提供列车定位的分辨率和精度以支持此项标准的性能和安全需求。对于传统的CBTC系统，列车的定位分辨率和精度参数如附件C所示。

CBTC列车定位决策功能应能自主初始化、自动检测，当每个装有CBTC设备的列车进入CBTC区域时对其进行定位，并且在CBTC设备故障时进行恢复，而不需要人工输入列车位置或列车长度数据。

CBTC列车速度决策功能可以充分地提供速度测量的分辨率和精度来支持此项标准的性能和安全需求。对于典型的CBTC系统，速度测量的分辨率和精度参数如附件C所示。

CBTC系统能够补偿在列车定位和速度决策中测量误差产生的影响。尤其是，如果CBTC列车定位/速度决策功能与车轮旋转相关，CBTC系统.......

6. Functional requirements

A CBTC system shall include the capability for providing ATP, ATO, and ATS functions. ATP functions shall provide fail-safe protection against collisions, excessive speed, and other hazardous conditions. ATP functions shall have precedence over both the ATO and ATS functions. ATO functions shall control basic operations that would otherwise be performed by a train operator and shall do so within the protection limits imposed by ATP. ATS functions shall provide system status information and the means to monitor and override the automatic control for various functions of the system. 

The CBTC train-to-wayside communications interface shall be sufficient to support all required ATP, ATO, and ATS functions. The data link shall provide continuous geographic coverage within CBTC territory and shall support train operations in tunnels, tubes, and cuts, on elevated structures, and at grade. The data link shall support bidirectional data transfer and shall exhibit sufficiently low latency to support the defined performance requirements. The data link shall include a protocol structure to support safe, timely, and secure delivery of train control messages.

6.1 ATP functions

All ATP functions shall be vital functions and shall be designed and implemented in accordance with 5.3. 

A CBTC system shall be capable of providing bidirectional ATP.

6.1.1 Train location/train speed determination

6.1.1.1 CBTC train location/train speed determination

CBTC train location/train speed determination shall be a required ATP function for any CBTC system configuration.

A CBTC system shall establish the location, speed, and travel direction of each CBTC-equipped train operating in CBTC territory. 

CBTC train location determination shall safely and accurately establish the location of both the front and rear of the train. The CBTC train location determination function shall provide sufficient train location resolution and accuracy to support the performance and safety requirements of this standard. Train location resolution and .......