新视野大学英语第四册第四单元ppt课件.ppt

ThemunicationsRevolutionBook4,municationsopticalfiber()/high-capacityopticalfiberlinks()cable()copperwire()digitalswitches()/digitalmodel()/digitalmobilephonesystems()wirelesstransmissionsystems()theInformationAge()aspider’municationlinks()(电缆)数字转换器/数字模式/()logon(to)/logout/off()theelectronicdata()/electron()paperlesstrading()radiotower()stringlinesacrossmountainridges()wirelesscall()fixedlines()信息高速公路进入(计算机)系统;登录/退出电子数据/电子(信号)&municationsdevicesareavailableinyourlife?meantoyou?,fromGreek,municationsatadistance”.Thefirsttrend:puters,namely,dramaticdecreasesinphysicalsize,plexity,:(or“fiberoptic”)oftenreferstothemediumandthetechnologyassociatedwiththetransmissionofinformationaslightpulses(光脉冲)-,wemeanthat ,philosophical,’,high-workthatwillcarryvoice,data,video,andotherformsofinformationallovertheworld,andthatwillmakeitpossibleforpeopletosende-mail,getup-to-the-minutenews,essbusiness,