智能运输系统.地面车辆用通信通道(CALM).卫星网络

[中文适用范围]： 本国际标准提供了在使用双向卫星通信的CALM（陆地移动通信接入）系统环境中建立、维护和终止ITS（智能交通系统）通信会话的定义和程序。 它定义了介质管理适配实体（MMAE）的操作，该实体提供了专有卫星通信介质与"ITS站管理"之间的管理接口。这使得"ITS站管理"能够了解通信介质的状态并控制接口，而无需ITS站应用程序了解卫星通信接口。还解释了"ITS站管理"预期使用的程序。 注1：CALM链路需要用于车辆与路边、车辆之间以及移动设备与固定基础设施点之间在中长距离上进行的准连续、长时间和短时间通信。 本国际标准定义了如何在ISO 21217定义的环境中运行的应用程序上下文中使用卫星通信系统连接和断开通信会话。 它支持点对点通信模式。广播卫星系统的支持在ISO 13183中定义，该标准为所有广播介质提供了通用方法。它支持与公共网络互连的卫星通信网络，以及通过互联网连接的网络和提供独立能力的网络。 注2：由于卫星系统有多个实例，其中大多数不能互操作，因此可能存在多个同时进行的卫星会话，每个会话形成一个单独的CALM介质（尽管差异可能仅在于车载设备内的软件）。 在可行的情况下，本国际标准通过参考适用的现有标准制定，并通过选择采用。不包括特定应用的上层，而是由应用标准（可能不是特定于技术的）驱动。 [外文原描述]： ISO 29282:2011 provides definitions and procedures for the establishment, maintenance and termination of an ITS (intelligent transport systems) communications session within a CALM (communication access for land mobiles) system environment using bi-directional satellite communications. It defines the operation of the medium management adaptation entity (MMAE), which provides the management interface between a proprietary satellite communications medium and the "ITS station management". This enables the "ITS station management" to know the status of the communications medium and control the interface without the need for applications at the ITS station to have any knowledge of the satellite communications interface. The procedures that the "ITS station management" expects to use are also explained. ISO 29282:2011 defines how to connect and disconnect a communication session using satellite communication systems in the context of an application operated within the environment defined in ISO 21217. It supports peer-to-peer modes of communication. Support for broadcast satellite systems is defined in ISO 13183, which provides a common approach for all broadcast media. It supports satellite communications networks that are interconnected with the public network, as well as those which connect via the internet and those which provide a stand-alone capability.