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随着电信运营商和互联网运营商不断进入视频和电视服务领域,有线电视运营商面临着向用户提供越来越多节目和内容的压力,其中的很多内容可能是长尾的(longtail)、冷门的内容。但网络频率资源却是昂贵稀有的,因此就需要有更好的方案来平衡这种供需关系。和传统的广播电视(视频)服务相比,交换式广播服务能够在使用更少带宽的情形下,提供更多的广播节目。在理论上,一个典型的750MHz有线电视网络可以向订户提供超过一千个的广播数字节目,而与之对比,如果是采用传统的广播技术,却只能为订户提供几百个节目。交换式广播服务比传统的广播服务所需的投入更多,这是因为它需要额外的QAM(正交幅度调制)调制器硬件、一种实时双向的网络以及具备额外软件的互动设备(如机顶盒等)。只有当系统的投入能够被新增加的营业收入平衡后,部署交换式广播服务才具有经济意义。交换式广播服务新增加的营运收入要么是通过新增节目数量而获得,要么是通过充分利用节省下来的带宽而产生。
As telecom operators and Internet operators continue to enter the video and television services area, cable operators are under pressure to provide users with more and more programs and content, many of which may be long-tailed, unpopular Content. However, network frequency resources are expensive and rare, so there is a need for better solutions to balance this supply-demand relationship. Compared with traditional radio and television (video) services, switched broadcast services can provide more broadcast programs with less bandwidth. In theory, a typical 750MHz cable television network could provide subscribers with more than a thousand broadcast digital programs, compared to only offering hundreds of subscribers if using conventional broadcast technology. Switching broadcast services require more investment than traditional broadcast services because it requires additional QAM modulator hardware, a real-time bidirectional network, and interactive devices with additional software such as set-top boxes Wait). The deployment of switched broadcast services is economically significant only if the system’s inputs are able to be balanced by the newly added revenues. The new operating revenue from switching broadcast services is either gained by adding new programs or by making full use of the savings in bandwidth.