通信工程专业英语

精品文档 1欢迎下载1欢迎下载 一 汉译英 1 时分多址 TDMA Time Division Multiple Address Time Division Multiple Access 2 通用无线分组业务 GPRS General Packet Radio Service 3 国际电报电话咨询委员会 CCITT 4 同步数字体系 SDH Synchronous Digital Hierarchy 同步数字序列 5 跳频扩频 FHSS frequency hopping spread spectrum 6 同步转移模块 STM synchronous transfer module 7 综合业务数字网 ISDN Integrated Services Digital Network 8 城域网 MAN Metropolitan Area Network 9 传输控制协议 互联网协议 TCP IP Transmission Control Protocol Internet Protocol 10 服务质量 QOS Quality of Service 11 中继线 trunk line 12 传输速率 transmission rate 13 网络管理 network management 14 帧结构 frame structure 15 移动手机 Mobile Phone 手机 Handset 16 蜂窝交换机 Cellular switches 电池开 关 cell switch cell 蜂房 17 天线 Antenna 18 微处理器 microprocessor 19 国际漫游 International roaming 20 短消息 short message 21 信噪比 SNR Signal to Noise Ratio 22 数字通信 Digital communication 23 系统容量 system capacity 24 蜂窝网 cell network cellular network Honeycomb nets 25 越区切换 Handover 26 互联网 internet 27 调制解调器 modem 28 频谱 spectrum 29 鼠标 Mouse 30 电子邮件 electronic mail E mail 31 子网 subnet 32 软件无线电 software defined radios 33 网络资源 network resources 二 英译汉 1 mobile communication 移动通信 2 Computer user 计算机用户 3 Frame format 帧格式 4 WLAN wireless local area network 无线局域网 络 5 Communication protocol 通信协议 6 Transmission quality 传输质量 7 Remote terminal 远程终端 8 International standard 国际标准 9 GSM 全球移动通信系统 Global System for Mobile Communications 10 CDMA 码分多址 Code Division Multiple Access 11 ITU 国际电信联盟 International Telecommunication Union 12 PCM pulse code modulation 脉冲编码调制 13 WDM 波分复用 Wavelength Division Multiplex 14 FCC 联邦通信委员会 Federal communications commission 15 PSTN 公用电话交换网 Public Switched Telephone Network 16 NNI 网络节点借口 Network Node Interface 17 WWW 万维网 World Wide Web 18 VOD 视频点播 Video On Demand 19 VLR 访问位置寄存器 Visitor Location Register 20 MSC 移动交换中心 Mobile Switching Centre 21 HLR 原籍位置寄存器 Home Location Register 22 VLSI 超大规模集成电路 Very Large Scale Integrated Circuits 23 Bluetooth technology 蓝牙技术 24 Matched filter 匹配滤波器 25 ADSL 非对称数字用户环路 Asymmetrical Digital Subscriber Loop 非对称数字用户线路 Asymmetric Digital Subscriber Line 26 GPS 全球定位系统 Global Position System 27 ATM 异步传输模式 Asynchronous Transfer Mode 精品文档 2欢迎下载2欢迎下载 精品文档 3欢迎下载3欢迎下载 三 汉译英 1 脉冲编码调制 PCM 依赖于三个独立的操作 抽样 量化和编码 PCM is dependent on three separate operations sampling quantizing and coding 2 像 TCP 和 IP 那样的协议已经被设计出来 当然 它们还需要被更新和维持 Protocols like TCP and IP have already been designed of course but they need to be updated and maintained 3 码分多址是一种前景广阔的宽带数字工作系统 One form of digital wide band operation which has good future potential is CDMA 4 互联网是可提供很多网络资源的最大的信息库 The internet is the largest repository of information which can provide very large network resources 5 开发蜂窝式移动电话系统并将其在许多城市中推广应用的原因之一是传统的移动电话系统存在容量有限 服务性 能差 频谱利用率低的缺点 One of many reasons for developing a cellular mobile telephone system and deploying it in many cities is the operational limitations of conventional mobile telephone system limited servile capability poor service performance and inefficient frequency spectrum utilization 6 来自发端借口不见的定时新号被加到数据调 制解调器上 以使计算机与数传机同步 在接收端 从数据流中取出 同步脉冲式计算机同步 Timing signals from the interface assembly at the transmitter are applied to the data modem to synchronize the computer and the data set At the receivers synchronization pulses are derived from the data stream to synchronize the computer 7 我们正处于通信网络革命的开始 越来越大的容量需求 各种各样的应用 以及服务质量正在对光网络提出巨大 的需求 We are at the beginning of a revolution in communications networks where increasing capacity variety of applications and quality of service are placing enormous demands on the optical network 8 目前在欧洲正在开发第三代移动通信系统 其目的是要综合第二代系统的所有不同业务并覆盖更广泛的业务 话 音 数据 视频 多媒体 范围 而且还要与固定电话网络的技术发展保持一致和兼容 The third generation mobile communication system currently being developed in Europe intended to integrate all the different services of the second generation system and cover a much wider range of broadband services Voice data video multimedia consistent and compatible with technology developments taking place within the fixed telecommunication networks 9 在现代对多媒体的描述中 我们所具有的技术已开始向人类具有的能力迈进 通过使用计算机技术 软件和其他 技术 如 CD ROM 不仅能将视频图像和音频综合在一起 而且可以与其他计算机用户进行交互工作 In the modern presentation multimedia we now have the technology that can begin to move towards an ability already held by the human beings in that by using computer technology software and other technology such as CD ROM not only can we bring together audio and visual images but interactive with other computer users 10 为弥补这些问题 要在基本结构中加入大量的高效中继线 高效中继线用于直接连接有大量的节点间通信业务量 的各交换中心 通信量常常是通过网络中可用的最低层次传送的 To compensate for these problems a large number of high usage trunks augment the basic architecture High usage trunks are used for direct connection between switching centers with high volumes of internodes traffic Traffic is always routed through the lowest available level of the work 11 光纤网络的革命刚刚开始 并正快速向未来的带宽无线 可靠和低费用的在线世界发展 The revolution of optical network is just beginning and is advancing very swiftly toward a future online world in which bandwidth is essentially unlimited reliable and low cost 12 实际设备通常使用 8kHz 的采样速率 而如果每个样值用 8 位码的话 则话路是由一个重复速率 64kHz 的脉冲流 来表示 Practical equipments however normally use a sampling rate of 8 kHz and if 8 digits per sample value are used the voice channel becomes represented by a stream of pulses with a repetition rate of 64 kHz 13 是由于 SDH 设备在这些方面的标准化 才提供了网络运营者所期望的灵活性 从而能低价高效地应付带宽方面的 增长并为后十年中出现的新的用户业务作好准备 It is the standardization of these aspects of SDH equipment that will deliver the flexibility required by network operators to cost effectively manage the growth in bandwidth and provisioning of new 精品文档 4欢迎下载4欢迎下载 customer services expected in the net decade 四 英译汉 1 The cellular concept is defined by two features frequency reuse and cell splitting Frequency reuse comes into play by using radio channels on the same frequency in coverage areas that are far enough apart not to cause co channel interference This allows handling of simultaneous calls that exceed the theoretical spectral capacity Cell splitting is necessary when the traffic demand on a cell has reached the maximum m and the cell is then divided into a micro cellular system The shape of cell in a cellular system is always depicted as a hexagon and the cluster size can be seven nine or twelve 蜂窝的概念由两个特点决定 频率复用和小区分割 在相邻覆盖区域足够远的而不至于引起共用信道干扰的 通过使 用同一频率的无线信道 频率再利用才起作用 这样可以出来同时出现的呼叫并超出理论频谱容量 当小区的业务需 求增到最大时 就要被划分 小区就要被划分成更小的蜂窝系统区域 蜂窝系统的小区形状常被描述成六边形 一群 小区数量可以是 9 个或 12 个 2 Before you can use the Internet you must choose a way to move data between the Internet and your PC This link may be a high speed data communication circuits a local area network LAN a telephone line or a radio channel Most likely you will use a Modem attached to your telephone line to talk to the Internet Naturally the quality of your Internet connection and service like many other things in life is dictated by the amount of money you are willing to spend Although all these services can well satisfy the needs of the users for information exchange a definite requirement is needed for the users Not only should the users know where the resources locate but also he should know some operating commands concerned 在使用 Internet 之前 必须使用一种方法在呢的 PC 机和 Internet 之间传递数据 这种连接的链路可以是高速 数据通道电路 局域网 电话线路或无线信道 最有可能的是 你使用 Modem 连到电话线上与 Internet 对话 当然 像生活中许多其他事物一样 与 Internet 连接服务和质量是由你花钱的数量来决定的 虽然这些所有的服务可以很好满足用户交换信息需要 但用户仍旧需要具有特定的先决条件 用户不但要知道信 息资源的位置而且要知道一些有关的操作命令 3 Packet switching achieves the benefits discussed so far and offers added features It provides the full advantage of the dynamic allocation of the bandwidth even when messages are long Indeed with packer switching many packets of the same message may be in transmission simultaneously over consecutive links of a path from source to destination thus achieving a pipelining effect and reducing considerably the overall transmission delay of the message as compared to message switching It lends to require smaller storage allocation at the intermediate switches It also has better error characteristics and leads to more efficient error recovery procedures as it deals with smaller entities Needless to say packer switching presents design problems of its own such as the need to reorder packets of a given message that may arrive at the destination node out of sequence 分组交换除具有以上讨论的有点之外 还具有一些特点 它提供带宽动态分配的全部优势 甚至当报文很长时依然如 此 由于有分组交换 一个报文的多个分组确定可以通过原点到终点通路中多个链路同时传送 因而道道 管道 传 送的效应 与报文交换相比 他大大的减少了报文整体传送时延 在中间交换设备中这种方式只需要较小的存储分配 区域 分组交换的误码特性较好 由于它只涉及很短的长度 因而导致更高效的纠错方式 当然 分组交换也有自身 设计上的麻烦 例如 当报文无序到达目的节点时 需要重新对该报文进行分组排序 4 As more and more systems join the Internet and as more and more forms of information can be converted to digital form the amount of stuff available to Internet users continues to grow At some points very soon after the nationwide Internet started to grow people began to treat the Net as a community with its own tradition and customs 随着越来越多的系统连接到互联网 越来越多的信息被转化为数字形式 互联网用户可利用的资料持续增长 在不久 的将来当国内互联网的规模增加到一定程度时 人们开始把互联网当做社区对待 并且拥有自己的传统和习惯 5 Three components are involved in a basic optical fiber system the light source the photo detector and the optical transmission line The optical light source generates the optical energy which serves as the information carrier similar to a radio wave source supplying electromagnetic energy at radio wave wavelengths as the information carrier The optical photo detector detects the optical energy and converts it into an electrical form The optical fiber transmission line is the equivalent of copper 精品文档 5欢迎下载5欢迎下载 wires and function as the conductor of optical energy 基本的光纤系统涉及到 3 个部分 光源 光检测器和光缆 光源产生的能力作为信息的载体 类似于具有电磁能的无 线电波用波长作为信息载体 光检测器检测光能并将其转化为电能的形式 光缆等效于铜线具有传导光能的作用 6 The fixed telephone service is global and the interconnection varies from coaxial cable to optical fiber and satellite The national standards are different but with common interfaces and interface conversion interconnection can take place For mobile the problem is far more complex with the need to roam creating a need for complex networks and system Thus in mobile the question of standards is far more crucial to success than fixed systems The GSM system is based on a cellular communications principle which was first proposed as a concept in the 1940s by Bell System engineers in the U S The idea came out of the need to increase network capacity and got round the face that broadcast mobile networks operating in densely populated areas could be jammed by a very small number of simultaneous calls The power of the cellular system was that it allowed frequency reuse 全球范围内的固定电话通过同轴电缆 光缆和卫星相连 尽管各国的通信标准不同 但是由于有共同的接口和接口转 换设备 互连问题得以解决 对于移动通信存在漫游问题 网络和系统就比较复杂 所以移动通信的标准问题就更关 键 1940 年有美国贝尔系统工程师提出的蜂窝通信原理是 GSM 系统的基础 其思路是在人口密集的区域由于一些同时发起 的呼叫导致网络拥塞 采用蜂窝系统可以增加系统的容量 蜂窝系统的优点在于频率的重复利用 7 The advantage of SDH are mainly reflected in the following 1 Lower network element costs With a common standard compatible equipment will be available from many vendors In a highly competitive market prices will be vary attractive 2 Better network management With better network management operators will be able to mote efficiently use the network and provide better service The concept of TMN Telecommunication Management Networks is under study by CCITT Some TMN standards defining management system interfaces already exist 3 Faster provisioning If new circuits can be software defined to use existing spare bandwidth then provisioning will be mush faster The only new connection needed will be from the customer s premises to the nearest network access node SDH 的优点是 1 较低的网络成本 由于具有共同的标准 许多供应商提供的设备可以兼容 激烈的时长竞争可以降 低成本 2 更好的网络管理 运营商有能力提供更有效的业务 电信网管标准正在由 CCITT 指定 定义管理接口的 相关标准已经出台 3 快速准备 如果新的电路可被软件来定义 利用现有的空闲频段从用户到最近的网络节点 接入的准备工作将更快 8 If we consider binary transmission the complete information about a particular message will always be obtained by simply detection the presence or absence of the pulse By comparison most other forms of transmission systems convey the message