Chapter Three Communications Channel Unit 10 a part 1 Notes to Text L Part4 Extensive Reading Part 2 Word Study Part5 Notes to Passage Part3 Practice on Text Part6 Practice on Passage 2021/2/20 P1
2021/2/20 P.1 Unit 10 Communications Channel Chapter Three @ Part 1 Notes to Text & Part4 Extensive Reading & Part 2 Word Study @ Part5 Notes to Passage @ Part3 Practice on Text @ Part6 Practice on Passage
a Part 1 Notes to text Communications Channel 1) It may be defined by a physical wire that connects communicating devices, or by a radio, laser, or other radiated energy source that has no obvious physical presence连接通讯设备的物理导线、无线电波、激光或其它那 些无形的辐射能源,都可说成是信道。 注释:该句是复合句,主语指代 a communications channel;谓 语是 may be defined;其状语由两个并列的介词短语构成,分别 REby a physical wire, a radio, laser, M by other radiated energy source;定语从句 Ithat connects communicating devices]bfpa physical wire; that has no obvious physical presence则修饰 other radiated energy source。 2021/2/20 P2
2021/2/20 P.2 @ Part 1 Notes to Text 1) It may be defined by a physical wire that connects communicating devices, or by a radio, laser, or other radiated energy source that has no obvious physical presence. 连接通讯设备的物理导线、无线电波、激光或其它那 些无形的辐射能源，都可说成是信道。 注释：该句是复合句，主语it指代a communications channel；谓 语是may be defined; 其状语由两个并列的介词短语构成，分别 是by a physical wire，a radio, laser, 和by other radiated energy source；定语从句that connects communicating devices修饰a physical wire；that has no obvious physical presence则修饰other radiated energy source。 Communications Channel
2). Information sent through a communications channel has a source from which the information originates, and a destination to which the information is delivered.通过信道发送的信息都有 个信息源和送达的目的地。 注释:该句中的 sent through a communications channel是过去分 词短语作定语,修饰主语 information; from which the information originates和 to which the information is delivered是介词前置的定 语从句,分别修饰两个宾语: a source和 a destination 2021/2/20 P3
2021/2/20 P.3 2）Information sent through a communications channel has a source from which the information originates, and a destination to which the information is delivered. 通过信道发送的信息都有一 个信息源和送达的目的地。 注释：该句中的sent through a communications channel是过去分 词短语作定语，修饰主语information; from which the information originates和to which the information is delivered是介词前置的定 语从句，分别修饰两个宾语：a source 和a destination
3) Although information originates from a single source, there may be more than one destination, depending upon how many receive stations are linked to the channel and how much energy the transmitted signal possesses.虽然信息产生于一个信息源,但 送达的目的地却可能不止一个,这往往取决于连接信道接收站的数量 和已发送信号所拥有的能量高低。 注释:连词 Although引导的是让步状语从句;该句的主句是 ethere may be more than one destination;其中短语 more than表示“不 止”,“多于”;现在分词短语用作伴随状语,介词upon的宾语是由 how many和 how much引导的宾语从句构成的。 4) It really consists of two sim plex channels, a forward channel and a reverse channel, inking the same points.其实全双工通道是 由两条单工信道构成的,其中一条是正向通道,一条是反向通道,它 们的连接点相同。 注释:主语此指代“全双工通道”;名词短语 a forward channel and a reverse channel是宾语 two simplex channels的同位语;现在分词 短语 lin king the same points是伴随状语 2021/2/20 SPaY End
2021/2/20 P.4 3）Although information originates from a single source, there may be more than one destination, depending upon how many receive stations are linked to the channel and how much energy the transmitted signal possesses. 虽然信息产生于一个信息源，但 送达的目的地却可能不止一个，这往往取决于连接信道接收站的数量 和已发送信号所拥有的能量高低。 注释：连词Although引导的是让步状语从句；该句的主句是there may be more than one destination；其中短语more than表示“不 止”，“多于”；现在分词短语用作伴随状语，介词upon的宾语是由 how many 和how much引导的宾语从句构成的。 4）It really consists of two simplex channels, a forward channel and a reverse channel, linking the same points. 其实全双工通道是 由两条单工信道构成的，其中一条是正向通道，一条是反向通道，它 们的连接点相同。 注释：主语It指代“全双工通道”；名词短语a forward channel and a reverse channel是宾语two simplex channels的同位语；现在分词 短语linking the same points是伴随状语。 End
Part 2 Word Study 1. channel n.信道 10 multibit n.多数据位 2. pathway n.路径;通道 1 .encapsulation n.压缩;包装 3. wire n.导线 12 acilitate v.使容易,使便利 4 laser n.激光 13. duplex adj,双工的 5. radiate v.辐射 14. simultaneously adv.同时地 6. presence n.存在 15 garbled adi.混乱的,引起误解的 7. originate v.起源;发端 16 .simplex adj.单工的 8. possess V.拥有 17 half-duplex adj半双工的 9 encapsulate v.压缩;打包 18. full-duplex adj全双工的 2021/2/20 P.5 End
2021/2/20 P.5 End 1. channel n. 信道 2. pathway n. 路径；通道 10.multibit n. 多数据位 11.encapsulation n. 压缩;包装 3. wire n. 导线 12.facilitate v. 使容易, 使便利 4.laser n. 激光 13.duplex adj. 双工的 5. radiate v. 辐射 14.simultaneously adv. 同时地 6. presence n. 存在 15.garbled adj. 混乱的，引起误解的 7. originate v. 起源；发端 16.simplex adj. 单工的 8. possess v. 拥有 17.half-duplex adj. 半双工的 9. encapsulate v. 压缩；打包 18.full-duplex adj. 全双工的 & Part 2 Word Study
Part3 Practice on Text Task 1: Listening training Dictation of some key words Directions: You will hear some key words twice, most of which are taken from the Word Study. Then finish the Crossword Puzzle. ( See you book p. 2. Dictation of some key expressions Directions: You will hear some key expressions twice, most of which are taken from this text. Then you are asked to complete the missing words 1)by a_physical 4)collection_ofbytes 2)radiated energy source 5)a radio station 3)multibit message units 6)message exchange 2021/2/20 P.6
2021/2/20 P.6 Task 1: Listening training Dictation of some key words Directions: You will hear some key words twice, most of which are taken from the Word Study. Then finish the Crossword Puzzle. (See you book p. ) 2. Dictation of some key expressions Directions: You will hear some key expressions twice, most of which are taken from this text. Then you are asked to complete the missing words. @ Part3 Practice on Text 1) by a ____________wire 2) radiated_______________ 3) ___________message units 4) ______________of bytes 5) a radio______________ 6) message______________ physical energy source multibit collection station exchange
Task 2. Read. Write and Translate Read and Reply Directions: Students are required to read aloud the whole text after the teacher. Then give short answers to the following questions a) What is the information represented by in a digital communications channel? In a digital communications channel, the information is represented by individual data bits, which may be encapsulated into multibit message units b)What is a collection of bytes grouped into? A collection of bytes may itself be grouped into a frame or other higher-level message unit. c)Which allows simultaneous message exchange in both directions, a half-duplex channel or a full-duplex channel? A full-duplex channel allows simultaneous message exchange in both directions. 2021/2/20 P7
2021/2/20 P.7 Read and Reply Directions:Students are required to read aloud the whole text after the teacher. Then give short answers to the following questions: a) What is the information represented by in a digital communications channel? b) What is a collection of bytes grouped into? Task 2: Read, Write and Translate In a digital communications channel, the information is represented by individual data bits, which may be encapsulated into multibit message units. A collection of bytes may itself be grouped into a frame or other higher-level message unit. A full-duplex channel allows simultaneous message exchange in both directions. c) Which allows simultaneous message exchange in both directions, a half-duplex channel or a full-duplex channel?
Read and Judge (f1) information sent through communications channel has only an source from which the information originates (F)2)A byte, which consists of sixteen bits, is an example of a message unit that may be conveyed through a digital communications channel (T )3)The message source is the transmitter, and the destination is the receiver T)4)Messages may flow in two directions, but never at the same time, in a half-duplex system. (T )5).It really consists of two sim plex channels, a forward channel and a reverse channel, linking the same points 2021/2/20 P 8 End
2021/2/20 P.8 ( )1) Information sent through a communications channel has only an source from which the information originates. ( )2) A byte, which consists of sixteen bits, is an example of a message unit that may be conveyed through a digital communications channel. ( )3) The message source is the transmitter, and the destination is the receiver. ( )4) Messages may flow in two directions, but never at the same time, in a half-duplex system. ( )5) It really consists of two simplex channels, a forward channel and a reverse channel, linking the same points. Read and Judge End F F T T T
Read and Complete Directions: Read the following short passage. Complete it by filling in the missing words A region B independently C hexagons D limiting E cell F local G coverage H completely I range J transmitters Mobile communication work by 1)'D transmitter powers. This restricts the 2) of communication to a smal 3)A, Outside this region, other 4)I can operated 5)B. Each region is termed a 6)E. These cells are often represented in diagrams as 7):C In practise the cell shape is determined by 8)E propagation characteristics. Together the cells will 9)Hcover the area supplied with mobile communication10)G 2021/2/20 .9y End
2021/2/20 P.9 Directions:Read the following short passage. Complete it by filling in the missing words. A. region B. independently C. hexagons D. limiting E. cell F. local G. coverage H. completely I. range J. transmitters Mobile communication work by 1)______ transmitter powers. This restricts the 2)_____ of communication to a small 3)_______. Outside this region, other 4)______can operated 5)______. Each region is termed a 6)_______. These cells are often represented in diagrams as 7)_______. In practise the cell shape is determined by 8)_______ propagation characteristics. Together the cells will 9)_______ cover the area supplied with mobile communication10)________. Read and Complete End D I A J B E C F H G
Read and Translate Directions: Put the following sentences into English, using the words or phrases given 1)五架飞机以五环图案为中心向各方飞开去。( radiate) Five planes radiated from the pattern of the five rings 2)将军在危急关头的出现稳定了军心。( presence) The captain s presence during the crisis had a calming effect in the army. 3)那位商业巨头在许多城市都有房产。( possess) The business giant possesses real estate in many cities 4)那个受过惊吓的孩子只能含糊地说出交通事故的经过。 (garbled) The frighten child could only give a garbled account of the traffic accident 5)这种建筑风格起源于明朝。( originate) The style of architecture originated from with the Ming dynasty 202120P10 End
2021/2/20 P.10 1)五架飞机以五环图案为中心向各方飞开去。（radiate） 2)将军在危急关头的出现稳定了军心。（presence） 3)那位商业巨头在许多城市都有房产。(possess) 4)那个受过惊吓的孩子只能含糊地说出交通事故的经过。 (garbled) 5)这种建筑风格起源于明朝。(originate) Read and Translate Directions:Put the following sentences into English, using the words or phrases given. End Five planes radiated from the pattern of the five rings. The captain’s presence during the crisis had a calming effect in the army. The business giant possesses real estate in many cities. The frighten child could only give a garbled account of the traffic accident. The style of architecture originated from / with the Ming dynasty