计算机英语计算机通信第七单元:计算机通信Telemunicationsallowspeoplearoundtheworldtocontactoneanother,toaccessinformationinstantly,andtomunicatefromremoteareas、Telemunicationsusuallyinvolvesasenderofinformationandoneormorerecipientslinkedbyatechnology,suchasatelephonesystem,thattransmitsinformationfromoneplacetoanother、Telemunicationsdevicesconvertsdifferenttypesofinformation,suchassoundandvideo,intoelectronicsignals、Thesignalscanthenbetransmittedbymeansofmediasuchastelephonewiresorradiowaves、电信使世界各地得人们得以互相联系,即刻获取信息,并从边远地区实施通信。电信通常涉及一个信息发送者和一个或多个接收者,她们通过电话系统等把信息从一地发送到另一地得技术相联系。电信设备将不同类型得信息,如声音和图像,转换成电子信号。然后,这些信号就可以通过电话线或无线电波等媒介进行发送。Whenasignalreachesitsdestination,thedeviceonthereceivingendconvertstheelectronicsignalbackintoanunderstandablemessage,suchassoundoveratelephone,movingimagesonatelevision,orwordsandpicturesonaputerscreen、Telemunicationsenablepeopletosendandreceivepersonalmessagesacrosstown,betweencountries,andtoandfromouterspace、Italsoprovidesthekeymediumfornews,data,information,andentertainment、信号到达目得地后,接收端得设备将电子信号转换回可以理解得信息,如电话中得声音、电视上得活动图像或计算机屏幕上得文字和图片。电信使人们能够在城镇不同地方、国家之间以及向外层空间和从外层空间发送和接收个人信息。电信也为新闻、数据、信息和娱乐提供了关键得媒介。Telemunicationsmessagescanbesentinavarietyofwaysandbyawiderangeofdevices、Themessagescanbesentfromonesendertoasinglereceiver(point-to-point)orfromonesendertomanyreceivers(point-to-multipoint)、Personalmunications,suchasatelephoneconversationbetweentwopeopleorafacsimile(fax)message,usuallyinvolvepoint-to-pointtransmission、Point-to-multipointtelemunicationsoftencalledbroadcasts,providethebasisformercialradioandtelevisionprogramming、电信信息可通过各种方式和设备发送。信息可由一个发送者发送给一个接收者(点对点),或者由一个发送者发送给多个接收者(点对多点)。个人通信,如两个人之间得电话对话或传真信息,通常涉及点对点得传输。通常称为广播得点对多点电信传输,为商业无线电和电视节目播送提供了基础。Telemunicationsbeginwithmessagesthatareconvertedintoelectronicsignals、Thesignalsarethensentoveramediumtoareceiver,wheretheyaredecodedbackintoaformthatthepersonreceivingthemessagecanunderstand、Therearevarietyofwaystocreateanddecodesignals,andmanydifferentwaystotransmitsignals、大家有疑问的，可以询问和交流电信以信息转换为电子信号为开端。然后,这