| 摘要 |
Service component files are received at an input (11) from one or more service operators. An encapsulation and multiplexing system (12) organizes service components (20-23, see FIG. 2) relating to a service sequentially in a burst. In a burst, the service components include content data of different data types. A timing data subsystem (14) produces data from which a receiver can determine the times of datacast of the service components within a burst. Metadata dependent on the data type of each service component is organized, separately from the content data, by a component analyser (15). The metadata can identify a class of receiver having the capability to decode the corresponding service component, or can identify the data type of the corresponding service component, or it identifies the corresponding service component using a unique identifier. The service components, the metadata and the timing data is datacast by a transmitter station (13) for reception by receiver terminals. The metadata can be datacast as part of the corresponding service component, for example in a header thereof, or on a different bearer to the service components. |
