Unit 15 Communication System,通信系统,Part Three Communication and Information Processing,Technical terms:,Preparing for the text:,Questions for text discussion: Take some examples about the application of communication in our daily lives. The telephones at our hands, the radios and televisions in our living rooms, the computer terminals with access to the Internet in our offices and homes, Communication through a wireless telephone keeps a car driver in touch with the office or home miles away. Communication keeps a weather forecaster informed of conditions measured by a multitude of sensors. 2. What basic elements does the communication system involve? Transmitter, and the channel, and receiver,1. transmitter 发射机 2. receiver 接收机 3. computer terminals 计算机终端设备 4. wireless telephone 无线电话 5. interfering signal 干扰信号 6. high seas 公海,3. Describe the function of a transmitter or a receiver. The purpose of the transmitter is to convert the message signal produced by the source of information into a form suitable for transmission over the channel. The receiver has the task of operating on the received signal so as to reconstruct a recognizable form of the original message signal for a user.,The main idea of this unit:,This unit mainly discusses the basic knowledge about communication system. (1) Communication enters our daily lives in many different ways. (2) There are three basic elements to every communication system, namely, transmitter, and the channel, and receiver. (3)Introducuce the function of communication system elements.,Technical terms:,Preparing for the text:,Questions for text discussion: Tell the advantages for mobile phone over fixed phone? convenient and flexible 2. What are the three basic parts for a cellular mobile telephone system? mobile services switching center (MSC), radio base station (BS) and mobile station(MS) 3. What are the functions of base stations?,1. cellular mobile telephone 蜂窝移动电话 2. mobile service switching center (MSC) 移动业务交换中心 3. base station(BS) 基站 4. mobile station(MS) 移动台 5. public switching telephone network (PTSN) 公共电话交换网,New Words,1.multitude n. 多数 (文) the multitude of its facets 它的很多方面 eg. Vast multitude of birds visit this lake in spring. 春天有大批的鸟飞临此湖. 2. facet n. 方面,(问题等的)一个方面 eg. There are many facets to this question. 这个问题有很多方面.,3. globe n. 地球 the globe= the earth 地球,世界 eg. travel round the globe 环球旅行 派 global adj. 全球性的,全世界的,包括一切的 eg. global warfare 世界大战 a global definition 总的定义 4.forecaster n. 预报员 派 forecast v. 预报,预测 eg. A weather forecaster is a person who forecast the weather. fore- (前缀) (时间或职位)前,预先 forebear=ancester 祖宗 forehead 额,5. encode vt. 编码 (文) The encoding of these symbols in a form that is suitable for transmission over a physical medium of interest. 派 decode vt. 解码器 6. sensor n. 传感器 (文) a multitude of sensors 一系列传感器 eg. Smoke sensors warned us of the fire. 烟雾探测器已向我们发出火警警报. 派 sensory adj. 感觉的,感受的,7. implicitly a. 含蓄的,内含的,绝对 (文) Communication involves implicitly the transmission of information. 通信本身涉及发射信息. eg. trust sb. implicitly 绝对信任某人 派 implicit adj. an implicit threat 暗示的恫吓 8. precision n. 精密度,精度 (文) a certain measure of precision 某个精确的物理量 派 precise adj. 精确的,一丝不苟的,9. destination n. 目的地 (文) the transmission of the encoded symbols to the desired de -stination 编码的信号传输到要求的目的地 eg. Tokyo was our final destination. 东京是我们的最终目的地. 10. degradation n. 降级,退化 (文) definable degradation in quality 质量上可解释的衰弱 派 degrade v. 贬低(某人),降低(某人)的身份 eg. degrade molecules into atoms 将分子降解为原子,11. imperfection n. 缺陷 (文) The degradation is caused by imperfections in the system. 这些衰弱是由系统的一些缺陷造成的. eg. My father never tolerated imperfection. 我父亲要求一切事情非尽善尽美不可. 派 imperfect adj. 有缺点的,有瑕疵的 perfection n. 完美,圆满 12. propagate v. 传播,宣传 (文) the transmitted signal propagates along the channel eg. The group started a magazine to propagate its ideas. 这伙人办了一本杂志来宣传他们的主张.,13. corrupt adj.被破坏的,混浊的,不可靠的 (文) the received signal is a corrupted version of the trans -mitted signal 接收到信号是传输信号及干扰的混合 eg. a corrput society 堕落的社会 14. version n. 译本,译文 eg. This is a sophisticated version of the old camera . 这是老式相机中的精致款式.,Expressions,1.sothat 非常以致于 eg. He so adores his daughter that he keeps buying them expensive toys. 他非常疼爱女儿，经常给她们买贵重的玩具。 2. computer terminals 计算机终端设备 3. be capable of 能够 eg. You are capable of doing everying well. be capable of= be able to 派 capability n. 能力,4. provide senses for 为提供感测 （文）Communication provides the senses for ships on the high seas. 5. keep in touch with 与保持联系 eg. We should keep in touch with each other after we graduate. 6. inform of 通知或报告某人 eg. Keep me informed of/about what happens. 有事随时通知我。 7. a succession of 一连串的 （文）a succession of processes 一连串的过程,8.be suitable for 适合 eg. This clothes is suitable for you. 9. be caused by 由引起的 eg. His heart disease is caused by smoking. 他的心脏病由吸烟引起的。 10. irrespective of 无论 eg. The laws apply to eve