随着广播电视编解码和传输设备IP化接口的广泛出现,基于TS over IP的信号传输体系架构越来越得到广泛关注。本文主要介绍了中央电视台基于TS over IP的播出信号编码压缩系统架构,并面向新媒体、传统地面站等不同类型的下游接收用户,分...随着广播电视编解码和传输设备IP化接口的广泛出现,基于TS over IP的信号传输体系架构越来越得到广泛关注。本文主要介绍了中央电视台基于TS over IP的播出信号编码压缩系统架构,并面向新媒体、传统地面站等不同类型的下游接收用户,分析阐述了IP节目流的传输分发方式。展开更多
随着科技的进步与数字时代的到来,传统有线数字电视节目分发与传输方式面临着前所未有的挑战。尤其是在当前三网融合的大背景下,异步串行接口(Asynchronous Serial Interface,ASI)结构的传输模式已经难以满足新业态模式的用户需求,更难...随着科技的进步与数字时代的到来,传统有线数字电视节目分发与传输方式面临着前所未有的挑战。尤其是在当前三网融合的大背景下,异步串行接口(Asynchronous Serial Interface,ASI)结构的传输模式已经难以满足新业态模式的用户需求,更难以支撑新业务领域的扩展。为应对这一挑战,微波总站作为广播电视业务传输机构,在广播电视节目的分发和传输中积极应用新技术,旨在提升业务的多样性,增强适应性,并拓展微波站的应用领域,从而推动微波事业的蓬勃发展。基于此,详细阐述广州市广播电视微波总站充分结合融媒体业务,对现有的电视节目分发与传输平台进行全面的改造的过程。改造过程中,摒弃了传统的ASI传输平台,采用基于网际互连协议(Internet Protocol,IP)组播技术的全新系统架构。这一创新的架构,不仅提升了系统的灵活性和可扩展性,更为微波总站承接更多的新业务和服务更广泛的用户群体提供技术支持。展开更多
Recent researches show that inter-session network coding could decrease the number of packets transmission and achieve higher throughput in wireless network compared with traditional forwarding mechanism. In most exis...Recent researches show that inter-session network coding could decrease the number of packets transmission and achieve higher throughput in wireless network compared with traditional forwarding mechanism. In most existing relay mechanisms based on inter-session network such as COPE, relay node demands to collect the messages from its neighbor nodes to get notice of which packets already overheard by them so as to determine whether there exists coding opportunity between or among forwarding packets. However, transmission overhead of this message collection and computing cost of opportunity determination will degrade the performance of these mechanisms. It is observed that coding opportunity at relay node is much more related with the local topology, and the opportunity of encoding three or more packets together is far less than that of encoding two packets together in wireless network with general density. Based on this, a new coding-aware routing mechanism, named TCAR, is proposed. TCAR ignores the oppommity of encoding three or more than three packets together. Each relay node maintains an encoding mapping table being established according to the result of its local topology detection, which can be used to calculate the path cost during routing setup phase, and determine that which two packets can be encoded together during the packets forwarding phase. In TCAR, instead of periodic messages collection, each relay nodes just need once local topology detection, and the encoding determination is much simpler than that of the former mechanisms. Simulation results show that compared with typical inter-session network coding mechanisms COPE and COPE-based routing, TCAR achieves 12% and 7% throughput gains, and keeps the minimum end to end delay.展开更多
文摘随着科技的进步与数字时代的到来,传统有线数字电视节目分发与传输方式面临着前所未有的挑战。尤其是在当前三网融合的大背景下,异步串行接口(Asynchronous Serial Interface,ASI)结构的传输模式已经难以满足新业态模式的用户需求,更难以支撑新业务领域的扩展。为应对这一挑战,微波总站作为广播电视业务传输机构,在广播电视节目的分发和传输中积极应用新技术,旨在提升业务的多样性,增强适应性,并拓展微波站的应用领域,从而推动微波事业的蓬勃发展。基于此,详细阐述广州市广播电视微波总站充分结合融媒体业务,对现有的电视节目分发与传输平台进行全面的改造的过程。改造过程中,摒弃了传统的ASI传输平台,采用基于网际互连协议(Internet Protocol,IP)组播技术的全新系统架构。这一创新的架构,不仅提升了系统的灵活性和可扩展性,更为微波总站承接更多的新业务和服务更广泛的用户群体提供技术支持。
基金Projects(61173169,61106036)supported by the National Natural Science Foundation of ChinaProject(NCET-10-0798)Program for New Century Excellent Talents in University,China
文摘Recent researches show that inter-session network coding could decrease the number of packets transmission and achieve higher throughput in wireless network compared with traditional forwarding mechanism. In most existing relay mechanisms based on inter-session network such as COPE, relay node demands to collect the messages from its neighbor nodes to get notice of which packets already overheard by them so as to determine whether there exists coding opportunity between or among forwarding packets. However, transmission overhead of this message collection and computing cost of opportunity determination will degrade the performance of these mechanisms. It is observed that coding opportunity at relay node is much more related with the local topology, and the opportunity of encoding three or more packets together is far less than that of encoding two packets together in wireless network with general density. Based on this, a new coding-aware routing mechanism, named TCAR, is proposed. TCAR ignores the oppommity of encoding three or more than three packets together. Each relay node maintains an encoding mapping table being established according to the result of its local topology detection, which can be used to calculate the path cost during routing setup phase, and determine that which two packets can be encoded together during the packets forwarding phase. In TCAR, instead of periodic messages collection, each relay nodes just need once local topology detection, and the encoding determination is much simpler than that of the former mechanisms. Simulation results show that compared with typical inter-session network coding mechanisms COPE and COPE-based routing, TCAR achieves 12% and 7% throughput gains, and keeps the minimum end to end delay.
