卫星传播

Finally, applications of the anomalous propagation of microwave in tropospheric ducts are discussed: in connection with concrete radar parameters, effects of ducts on radar range and detection performance are discussed, the results obtained are of great value for the overall design of radar systems; by use of the interference standards of ITU-R, the co-ordination area of satellite earth-station under tropospheric ducts environment is studied ; by explaining the relationship between evaporation duct and advection fog, a new way to forecast sea advection fog from evaporation duct is provided.

最后讨论了对流层大气波导环境下电波异常传播特性的应用：结合具体的雷达系统参数，模拟计算了大气波导对雷达作用距离及发现概率的影响，对雷达系统的总体设计具有重要的参考价值；对表面大气波导环境下的卫星地球站通信协调区域进行了确定，从理论上很好地给出了协调距离量级的概念，为卫星地球站与地面微波站之间的协调提供了依据和参考；分析了利用海面蒸发波导来快速预测平流海雾的新方法，完善了平流海雾的预报方法，对海上安全作业和生产具有重要的意义。

The application of DVB system which started with satellite living broadcast system was adoptted by CATV gradually. By the growing up of Internet, DVB system based on llnternet became the research object of researchers and engineers. However, narrow band and high error rate of Internet limited the application of DVB system which should transport lots of data on network.

DVB体系的应用起始于直播卫星系统，后来逐渐被有线电视系统采用，由于Internet的崛起，有人开始了基于Internet的DVB系统的研究，可是Internet带宽低，错误率高，这些Internet网络固有的局限性，限制了需要大量数据的传播的DVB系统的广泛应用。

In the Internet age, TV communication is very much"narrowcast", and the content has to be tailored to the needs of the audience.

从接收角度讲，未来电视传播既可通过有线电视、卫星电视直接接收，又可通过互联网接收，传输渠道异常畅通，无远弗界、无孔不入。

B communication by an establishment of a transmission or retransmission embodying a performance or display of a nondramatic musical work intended to be received by the general public, originated by a radio or television broadcast station licensed as such by the Federal Communications Commission, or, if an audiovisual transmission, by a cable system or satellite carrier, if

b一个设施传播或二次传播从一个得到像联邦通讯委员会这样的机构许可的广播或电视站播放的(如果是视听传输，则通过有线系统或卫星电波来播放)、旨在让大众接收到、含非戏剧音乐作品的表演或展示的行为，如果--。

Communication by an establishment of a tra mi ion or retra mi ion embodying a performance or di lay of a nondramatic musical work intended to be received by the general public, originated by a radio or television broadcast station lice ed as such by the Federal Communicatio Commi ion, or, if an audiovisual tra mi ion, by a cable system or satellite carrier, if

一个设施传播或二次传播从一个得到像联邦通讯委员会这样的机构许可的广播或电视站播放的（如果是视听传输，则通过有线系统或卫星电波来播放）、旨在让大众接收到、含非戏剧音乐作品的表演或展示的行为，如果

Some of the specific effects of space weather on Earth systems include interference with short wave radio propagation, problems with electric power grids, the decay of satellite orbits, and radiation hazard for satellites and for astronauts during some phases of space missions.

太空天气对地球系统所产生的影响包括对短波无线电传播的干涉，电力输送线路的问题，卫星运行寿命的减少，以及对太空任务某些时段的卫星与太空人造成的辐射危险。

China Broadcasting Corporation is the Wholly-owned subsidiary of Wireless Radio Administration of SARFT. The company specializes in China Mobile Multimedia Broadcasting network construction, operation, system design, the development of relevant technology of Satellite broadcasting and the service of signal transmission.

中广传播有限公司为国家广电总局无线电台管理局的全资公司，主要承担我国卫星移动多媒体广播电视CMMB项目的投资和运营、系统设计、广播卫星相关技术开发和信号传输服务。

The more strict equations of the GPS static absolute position are obtained,by considering the effect of the transmission of signal in earth's gravitation,on the condition that the earth's gravitation is static and spherically symmetric.

笔者认为导航卫星在地球周围的引力场中运行，因此要作精确的定位就必须考虑时空的弯曲结构对信号传播的影响，进而对GPS系统的静态绝对定位方程做出修正。1 GPS静态绝对定位原理如图1所示。

Tendencies in the development of digital television broadcasting are:(1) Stereophonic or two-language sound transmission with television in existing analog TV system,(2) Digital direct satellite broadcasting;(3)Digital high definition television Broadcasting.

数字式电视卫星广播的发展趋势是：（1）在现有的模拟式基础上传播高音质立体声或双语音电视广播；（2）数字式直接卫星电视广播；（3）高清晰度数字式电视广播。

In 1962, at the chilliest part of the cold war and just after the launch of Sputnik had heralded the space age, he discussed in "Profiles of the Future" the implications of transatlantic satellite radio and television broadcasts, with information raining down on previously isolated parts of the world.

预告太空时代到来的苏联人造地球卫星发射不久、冷战最严峻的年代1962年，他在《未来的轮廓》里探讨了跨大西洋卫星无线电及电视转播对于把资讯传播到原本互不关联的世界各地的意义。

As she looked at Warrington's manly face, and dark, melancholy eyes, she had settled in her mind that he must have been the victim of an unhappy attachment.

每逢看到沃林顿那刚毅的脸，那乌黑、忧郁的眼睛，她便会相信，他一定作过不幸的爱情的受害者。

Maybe they'll disappear into a pothole.

也许他们将在壶穴里消失