SDI over IP关键技术研究

SDI over IP是电视中心基础架构IP化的基础性支撑技术,对于加速传统媒体与新媒体融合发展有至关重要的作用.本文将简要介绍SDI over IP技术及其应用,详细阐述该技术应用最为广泛的国际标准,重点分析关键技术的实现方法,并讨论该技术影响传输质量的主要因素.     

IP化4K超高清播出技术探讨

4K超高清信号的高分辨率、高帧频对播出系统的带宽要求较高。IP化可以有效解决数字分量串行接口(Serial Digital Interface,SDI)架构的带宽瓶颈,代表着今后电视制播业务的发展方向。基于此,分析IP化的诸多优势,探讨SDI over IP的技术标准、关键技术以及IP化4K超高清播出系统的基本架构和播出流程。     

中央电视台新址新闻IP收录平台简介

中央电视台新址新闻IP收录系统利用组播技术传输TS over IP流,采用以太网络设计架构将组播数据流进行解码和编码,将产生的媒体文件存储在核心存储上并具有组播流的实时监测功能。本文介绍了该系统的技术要点和应用情况。     

基于PXA255的VoIP语音传输系统研究

文章研究IP语音传输系统的总体架构,实现了一个基于PXA255处理器的嵌入式IP电话终端硬件平台,为该平台建立了一个优化的嵌入式Linux环境,并研究基于GSM 06.10语音编解码实现,设计了一个IP语音实时传输系统,实现了IP语音的网络实时传输功能.     

SDI和IP融合电视播出平台设计

本文以浙江广电集团好易购电视购物频道SDI和IP融合电视播出平台设计为基础,从总体框架、软件架构、业务流程、SDI播控平台、IP播控平台等方面探讨建设SDI和IP融合播出平台的技术路线和关键技术,旨在探索电视频道SDI和IP融合播出系统的架构思路,分享融合技术平台的设计经验.     

SDI+IP混合架构的播总控系统设计

近年来,广播电视技术转型向网际互连协议（Internet Protocol,IP）化发展的进程逐渐加快,基于IP架构的电视技术系统必将取代传统串行数字接口（Serial Digital Interface,SDI）架构,成为未来电视技术的发展方向。对以互联网协议网关（Internet Protocol Gateway,IPG）作为关键设备搭建“SDI+IP”混合架构系统的设计方案进行深入分析,阐述电视技术系统从SDI向IP技术转型过程中尽可能实现平稳过渡的思路。     

一种高精度PTP时钟同步方法及应用

PTP是实现网络精确时钟同步的热门技术之一,在工业以太网领域应用广泛.在IP流媒体传输领域,时钟同步至关重要.因此,介绍PTP时钟同步原理,提出一种时钟同步的具体实现方法,并将此方法应用于SMPTE ST 2110标准的SDI over IP技术,取得了满足产品实际应用的高精度时钟同步效果.     

演播室IP化架构浅析

本文介绍了国际SDI over IP的发展现状和总台超高清IP化的进程,分析了演播室IP化架构的模型,比较IP化架构网络构建的核心调度方案和边缘调度方案,并浅述部分IP化关键技术。     

基于TS over IP的电视台播出信号传输和分发实践

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。     

杭州亚运会总控IP信号调度浅谈

本文介绍了中央广播电视总台在转播杭州亚运会赛事时,总控外场系统在SDI和IP混合播出信号的架构下,如何实现IP信号的调度与分发。本次移动主控使用了两套基于IP架构的矩阵进行信号调度传输,通过不同的网络控制系统,完成信号的调度与分发。     

Progress in electrophotography in Western Europe

A review is given of the progress in electrophotographic science and technology in Western Europe during the years 1967 to early 1971. University research work is mainly directed towards two areas: 1) the electrical and physical properties of photoconductors, such as selenium, chalcogenides, oxides, and organic materials; and 2) the sensitization of these photoconductors. Industrial research teams report on the preparation of electrophotographic layers on development and on image evaluation. A bibliography including scientific papers and patents published on this subject during said period completes this review.     

智能通信在楼宇自控系统中的应用

随着计算机技术、控制技术、通信技术及信息技术的飞速发展,人们对生活、办公环境安全性、舒适性的要求日渐增长,智能建筑应运而生。楼宇自动化控制系统是智能建筑的一个重要组成部分。通过结合具体的智能楼宇控制工程项目,在介绍系统概况的基础上,给出了系统的总体设计方案及子系统的监控方案,具有一定的实用价值。     

Advances in millimeter-wave subsystems in Japan

The authors describe the development trends and results of millimeter-wave systems in Japan in such fields as communication, radar, and measurement systems. The applications included are the W-40G waveguide transmission communication system, an automobile traffic control system using the 60-GHz band, a collision avoidance radar system for an automobile, a plasma electron density measuring system, and satellite communication. The authors describe the development of devices such as high-power FET amplifiers, traveling wave tube amplifiers (TWTAs), IMPATT amplifiers, low-noise amplifiers, and monolithic microwave integrated circuit (MMIC) devices used in constructing the millimeter-wave systems     

General Trend in Electrical Communications in Japan

Systems are currently being designed for higher reliability and greater economy. Larger transmission capacity is required to meet a rapid increase in recent communication demands instigated by the introduction of video and information communications facilities. More flexibility, to deal with the variety of communication modes to come, and smaller hardware dimensions, to overcome situations caused by the high population density, seem to be particularly sought in the communication technology of Japan. Research and development concentrate on these objectives. The following is an explanation of the present state of the art and general trends in this country.     

Progress in display-device development in Western Europe

A review of the basic research and industrial development of display devices in Western Europe during the years 1968 to early 1973 will be given. The display types considered are: 1) active displays such as cathode ray tubes, light-emitting diodes, electroluminescence cells, and gas discharge devices, and 2) passive displays such as laser displays, light valves, and ferroelectric and liquid-crystal devices.     

Designing in reliability in advanced CMOS technologies

Assessment of design implications due to degradation of CMOS devices is increasingly required in the latest technologies. This paper presents selected topics relevant to realize an efficient design-in reliability methodology in the latest generation CMOS technologies. NBTI is discussed in terms of characterization using On-The-Fly (OTF) methodology. Extension of OTF method is discussed using bias patterns to gain insights into NBTI under analog operation. A reliability simulation methodology is discussed against requirements for optimization and integration within an existing design flow. The features of this methodology are illustrated using some simple design examples.     

Switching conduction in ion-irradiated layers in GaAs

Experiments have been performed to investigate whether switching phenomena are observable in ion-irradiated GaAs. It is found that the V/I characteristics of H2+-and N+-irradiated layers show both negative resistance and switching from a high resistance to a low resistance state. Ion irradiation may thus be a useful method of fabricating switching devices.     

Electricity in China-generation in the People's Republic

Before the establishment of the People's Republic, China was a semi-colonial, semi-feudal society plagued by foreign interventions and internal power struggles. It was against this background that the electrical industry went through its infancy. Today, the People's Republic of China is facing an acute energy shortage, posing a problem which must be quickly overcome if the country's rapid industrialisation is to continue as planned. The author presents a brief history of power generation in China from 1949 to 1983 and examines possibilities for the future