现代移动通信英语.doc

现代移动通信 在当今高度信息化的社会，信息和通信已成为现代社会的“命脉”。信息的交流主要依赖于计算机通信，而通信作为传输手段，与传感技术、计算机技术相互融合，已成为21世纪国际社会和世界经济发展的强大动力。为了适应时代的要求，新的一代移动通信技术应时而生，新的一代移动通信技术即人们称之第三代的核心特征是宽带寻址接入到固定网和众多不同通信系统间的无隙缝漫游，获取多媒体通信业务。 随着时代的进步、科技的创新、人们的生活要求的提高，移动通信技术更新换代速度相当惊人，差不多每隔十年移动通信技术就发生一次变革性换代，从上个世纪80年代的“大哥大”到现在的3G手机，其间发生了两次移动通信技术的变革，从1G的AMPS过渡到2G的GSM，从GSM到IMT-2000（即3G技术）。就我所知现代的移动通信技术有以下几方面的重要技术：1.宽带调制和多址技术2.频谱利用率提升技术3.软件无线电技术4.软件无线电技术5.网络安全和QoS现代移动通信技术发展的七个新趋势:一、移动管理已从终端管理向个人管理和智能管理发展二、网络已从同步的数字电路向异步的数字分组和异步传递方式(ATM)发展;三、软件的开发已从算法驱动到面向过程和面向目标的趋势发展;四、信息处理已从话音发展到数据和图像;五、无线频谱的处理已从窄带模拟向窄带CDMA发展;六、计算机已从集中式处理发展到分布式服务器和智能化处理;七、半导体器件已从每芯片16兆门/150MHz速率的VLSI发展到0.5千兆门/350MHz速率的VLSI和2千兆门 /550MHz速率的 VLSI。在这种趋势的引导下，移动通信业务迅猛发展，它满足了人们在任何时间、任何地点与任何个人进行通信的愿望。移动通信是实现未来理想的个人通信服务的必由之路。在信息支撑技术、市场竞争和需求的共同作用下，移动通信技术的发展更是突飞猛进，呈现出以下几大趋势：1)网络业务数据化、分组化；2)网络技术宽带化；3)网络技术智能化；4)更高的频段；5)更有效利用频率；6)各种网络趋于融合。了解、掌握这些趋势对移动通信运营商和设备制造商均具有重要的现实意义。Modern mobile communication technologyIn now highly the informationization society, the information and the correspondence have become the modern society “the life”. The information exchange mainly relies on the computer correspondence, but corresponds takes the transmission method, with the sensing technology, the computer technology fuses mutually, has become in the 21st century the international society and the world economic development powerful engine. In order to of adapt the time request, the new generation of mobile communication technology seasonable and lives, the new generation of mobile communication technology is the people said that third generations core characteristic is the wide band addressing turns on non-gap roaming between the rigid network and numerous different communications systems, gains the multimedia communication services.Along with the time progress, the technical innovation, peoples life requests enhancement, the mobile communication technology renewal speed is quite astonishing, almost every other ten year mobile communication technology has a transformation update, from the 1980s “the mobile phone” to presents 3G handset, during has had two mobile communication technology transformation, transits from 1G AMPS to 2G GSM, from GSM to IMT-2000 (i.e. 3G technology). Knows modern on me the mobile communication technology to have the following several aspect important technology:1. wideband modulation and multiple access technique2. frequency spectrum use factor lift technique3. software radio technology4. software radio technology5. network security and QoS modern mobile communication technological development seven new tendencies : First, mobility management already from terminal management to individual management and intelligent management developmentSecond, network already from synchronized digital circuit to asynchronous digital grouping and asynchronous transfer mode (ATM) development;the three, softwares developments actuated from the algorithm to the procedure-oriented and face the goal tendency development;the four, information processing have developed from the voice to the data and the image;five, wireless frequency spectrum processing already from narrow band simulation to the narrow band CDMA development;the six, computers have developed from central processing to the distributional server and intellectualized processing;the seven, semiconductor devices have developed from each chip 16,000,000,000,000 /150MHz speed VLSI to 0.5 /350MHz speed VLSI and 2,000,000,000,000,000 /550MHz speed VLSI. Under this tendencys guidance, the mobile service rapid development, it satisfied the people in any time, any place to carry on the correspondence with any individual the desire. The mobile communication realizes in the future the ideal person-to-person communication service way that must be taken. In the information support technology, the market competition and under the demand combined action, the mobile communication technologys development is progresses by leaps and bounds, presents the following several general trends: 1) network service digitization, grouping; 2) networking wide band; 3) networking intellectualization; 4) higher frequency band; 5) more effective use frequency; 6) each kind of network ten