2009-7-27 P,1
Unit 6
Telecommunication Technology
Chapter Three
&Part4 Extensive Reading@ Part 1 Notes to Text
@Part5 Notes to Passage& Part 2 Word Study
@Part3 Practice on Text @Part6 Practice on Passage
Chapter Study Tasks（ 3）
In this chapter,you will be able to
— Identify the key concepts of telecommunication
— Learn the basics of data and serial communications
— Get the general ideas of the text and the extensive reading
— Complete all the practice required
2009-7-27 P,2
@ Part 1 Notes to Text
1) In modern times,this process typically involves the
sending of electromagnetic waves by electronic
transmitters,but in earlier years it may have involved
the use of smoke signals,drums or semaphore,在现代，
这种传递的典型方式就是使用电子发射器发送电子波。而在较早的年代，传递方式可能用的是烟火讯号、击鼓声和旗语通讯法注释,注意 this process指代的是前文说的信号传递方式 ； 第二分句中的主语 it依然是指信号传递方式。
Key Concepts of Telecommunication
2009-7-27 P,3
2) Early inventors in the field include Alexander Bell,
Guglielmo Marconi and John Logie Baird,通信领域中的早期发明家有贝尔、马可尼和贝尔德。
注释,Bell,Alexander Graham，（ 1847-1922），美国发明家；
Guglielmo Marconi（ 1874— 1937），意大利物理学家； Baird，
John Logie，（ 1888-1946），英国电视发明家。
3) Telecommunication is an important part of the world
economy with the telecommunication industry's revenue being
placed at just under 3% of the gross world product,由于电信业的收入差不多占了世界总产值的 3%，所以电信是世界经济的一个重要部分。
注释,介词短语 with… 用作状语，表原因。现在分词短语 being
placed… 则是宾语补足语。
2009-7-27 P,4
4) This is to combat attenuation that can render the signal
indistinguishable from noise,这是为了防止信号衰减，而这种衰减则是由噪音导致的信号模糊。
注释,this指上文所说的必须要有一个放大器或转发器；不定式 to
combat attenuation是表语。
5） Alternatively,one could allocate each channel a recurring
segment of time over which to broadcast — this is known as
time-division multiplexing and is sometimes used in digital
communication,作为选择，你也可以给每个通道分配一个专门用来播放的循环时间段 — 这就是所谓的时分多址，这种技术有时候被用于数字通信。
注释,注意动词 allocate后面带的是双宾；短语 over which to
broadcast中的 which指代 a recurring segment of time。
End
2009-7-27 P,5 End
1,semaphore n,旗语通讯法 11.repeater n,转发器
2,gross n,总值 12.amplify v,放大,增强
3,analogue n,模拟 13.combat v,抗击 ; 防止
4,discrete adj,离散的 14.attenuation n,衰减
5,degrade v,降低 … 质量 15.render v,致使；造成
6,threshold n,极限 16.allocate v,分派,分配
7,intact adj,完整无缺的 17.recur v,循环
8,transceiver n.无线电收发机,收发器 18.segment n,段，节
9,router n,路由器 19.modulation n,调制
10,route v,发送 20.bluetooth n,蓝牙技术
& Part 2 Word Study
2009-7-27 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) ________________of signals
2) smoke______________
3) __________________networks
4) the gross________________
5) discrete________________
6) an analogue______________
transmission
signals
public telephone
world product
values
waveform
2009-7-27 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 may telecommunication have involved in early time?
b) Why do we say that telecommunication is an important part
of the world economy?
Task 2,Read,Write and Translate
It may have involved the use of signals,drums or semaphore.
Because the telecommunication industry's revenue is
placed at just under 3% of the gross world produc
A digital network may consists of one or more routers that route
data to the correct user,while an analogue network may consist
of one or more switches that establish a connection between
two or more users.
c) What is the difference between a digital networks and an
analogue network?
2009-7-27 P,8
( )1) Telecommunication is the transmission of signals over a
short time for the purpose of communication.
( )2) Telvevision,radio and telephone are devices that are used to
assist the process of widespreading telecommunication.
( )3) Telecommunication system mainly consists of a transmitter
and a transmission medium.
( )4) Digital signals are much better than analogue signals.
( )5) Both digital signals and analogue signals are disturbed by
noise when transmitted over a long distance.
Read and Judge
End
F
T
F
T
T
2009-7-27 P,9
Directions:Read the following short passage,Complete it by filling in the missing words.
A.receiver B,a phone line C,telecommunication D,between E,called
F,numerous G,because H,transmitter I,mobile J,systems
Consider a radio broadcast,In this case the broadcast tower is the
1)________,the radio is the 2)________and the transmission medium
is free space,Often telecommunication 3)________are two-way and a
single device acts as both a transmitter and receiver,or transceiver,
For example,a 4)________ phone is a transceiver.
Telecommunication over 5)________is called point-to-point
communication 6)________it is between one transmitter and one
receiver,7)________through radio broadcasts is
8)________broadcast communication because it is 9)________one
powerful transmitter and 10)________receivers
Read and Complete
End
H A
J
I
B
G
C
E D
F
2009-7-27 P,10
1) 她受到的良好教育培养了她精通英语的能力。（ shape）
2) 这一笔钱是用于贫困儿童的学费的 。 (allocate)
3) 中华民族是由汉族和其它五十六个少数民族构成的。 (consist of)
4) 昨天晚上台湾海峡的台风使海难再次发生 (recur) 。
5) 有很多政府高官涉嫌这次贿赂丑闻。 (involve)
Read and Translate
Directions:Put the following sentences into English,using the words or phrases given.
End
Very good education she recived has shaped her proficiency in
English.
This amount of money is allocated for the poor children’ s schooling.
The Chinese nationality consists of Han nationality and other
fifty-six minorities.
The typhoon in the Taiwan Straits made the wreck
recur yesterday evening.
Many highly-ranking government officers are involved
in the bribery scandal.
2009-7-27 P,11
Optical Fiber Cables
In practical fibers,the cladding(外层 )is usually coated with a
tough resin buffer layer(树脂保护层 ),which may be further
surrounded by a jacket layer(套层 ),usually plastic,These layers
add strength to the fiber but do not contribute to its optical(光的 )wave guide properties,Rigid(刚硬的 )fiber assemblies
sometimes put light-absorbing ("dark") glass between the
fibers,to prevent light that leaks out of one fiber from entering
another,This reduces cross-talk between the fibers,or reduces
flare in fiber bundle imaging applications.
For indoor applications,the jacketed fiber is generally
enclosed,with a bundle of flexible fibrous polymer(聚合物 )
strength embers like Aramid (e.g,Twaron or Kevlar),in a
lightweight plastic cover to form a simple cable,Each end of
the cable may be terminated with a specialized optical fiber
connector to allow it to be easily connected and disconnected
from transmitting and receiving equipment.
&Part4 Extensive Reading
2009-7-27 P,12
For use in more strenuous(艰辛的 )environments,a much more robust
cable construction is required,In loose-tube construction the fiber
is laid helically(螺旋形地 )into semi-rigid tubes,allowing the cable to
stretch without stretching the fiber itself,This protects the fiber
from tension during laying and due to temperature changes,
Alternatively the fiber may be embedded in a heavy polymer jacket,
commonly called "tight buffer" construction,These fiber units are
commonly bundled with additional steel strength members,again
with a helical twist to allow for stretching.
Another critical concern in cabling is to protect the fiber from
contamination(污染物 ) by water,because its component hydrogen
(hydronium) and hydroxyl(羟基 ) ions can diffuse(扩散 )into the fiber,
reducing the fiber's strength and increasing the optical attenuation,
Water is kept out of the cable by use of solid barriers such as
copper tubes,water-repellant jelly(防水胶 ),or more recently water
absorbing powder,surrounding the fiber.
2009-7-27 P,13
Finally,the cable may be armored(用装甲保护 )to protect it from
environmental hazards,such as construction work or gnawing
(咬,啃 ) animals,Undersea cables are more heavily armored in
their near-shore portions to protect them from boat anchors,
fishing gear,and even sharks,which may be attracted to the
electrical power signals that are carried to power amplifiers or
repeaters in the cable.
Modern fiber cables can contain up to a thousand fibers in a
single cable,so the performance of optical networks easily
accommodates even today's demands for bandwidth on a
point-to-point basis,However,unused point-to-point potential
bandwidth does not translate to operating profits,and it is
estimated that no more than 1% of the optical fiber buried in
recent years is actually 'lit'.
2009-7-27 P,14
Modern cables come in a wide variety of sheathings(护套 )and
armor,designed for applications such as direct burial in
trenches,dual use as power lines,installation in conduit(管道 ),
lashing to aerial telephone poles,submarine installation,or
insertion in paved streets,In recent years the cost of small
fiber-count pole mounted cables has greatly decreased due
to the high Japanese and South Korean demand for Fiber to
the Home (FTTH) installations.
End
2009-7-27 P,15
@Part5 Notes to Passage
1) In practical fibers,the cladding is usually coated with a tough
resin buffer layer,which may be further surrounded by a jacket
layer,usually plastic,实际上光纤的外层通常涂了一层坚韧的树脂保护层，树脂保护层或许还会再用一个套层包住，通常是塑料套层。
注释,介词短语 with a tough resin buffer layer 是方式状语，修饰谓语动词； which may be further surrounded by a jacket layer是非限制性定语从句，先行词是 a jacket layer。
2) Rigid fiber assemblies sometimes put light-absorbing ("dark")
glass between the fibers,to prevent light that leaks out of one
fiber from entering another.有时，坚硬的光纤装配将吸光（黑色）
玻璃介于光纤之间，这样才能防止光从一条光纤中渗漏入另一条光纤。
注释,不定式 to prevent light that leaks out of one fiber from
entering another既可用作目的状语，也可用作结果状语； that
leaks out of one fiber是定语从句，修饰 light。
2009-7-27 P,16 End
3) In loose-tube construction the fiber is laid helically into semi-
rigid tubes,allowing the cable to stretch without stretching
the fiber itself.在宽松管状结构中，光纤成螺旋形地被放入半坚硬的管道中，使电缆拉直，而不会拉直光纤。
注释,现在分词短语 allowing the cable to stretch without
stretching the fiber itself是伴随状语。
4) Undersea cables are more heavily armored in their near-shore
portions to protect them from boat anchors,fishing gear,and
even sharks,which may be attracted to the electrical power
signals that are carried to power amplifiers or repeaters in the
cable,海底电缆在靠海岸部分防护得更为坚实，以防止船锚，鱼具、
甚至可能是鲨鱼的侵害。这些东西都有可能被电能信号所吸引，这些信号在电缆中被传输给功率放大器或转发器。
注释,不定式短语 to protect them from boat anchors,fishing gear,
and even sharks是目的状语； which引导的是非限制性定语从句，
先行词是 boat anchors,fishing gear和 sharks。
2009-7-27 P,17
1.Listening Challenge
Spot Dictation
Directions,The following passage will be heard 3 times,During the second time,you
are required to put the missing words or phrases in the numbered blanks according to
what you hear,The third time is for you to check your answers,Now the passage
begins.
Modulation can also be used to transmit the information of
analogue 1)________ at higher frequencies,This is 2)________
because low-frequency 3)________ signals cannot be effectively
4)____________ over free space,Hence the information from a low-
frequency analogue signal must be superimposed on a higher-
frequency signal (known as a carrier wave) before transmission.
There are several different 5)_____________ schemes available to
6)________ this (two of the most basic being amplitude modulation
and 7)___________ modulation),An example of this 8)________ in
action is a DJ's voice being superimposed on a 96 MHz carrier
9)________ using frequency modulation (the voice would then be
received 10)__________ as the channel,96 FM” ).
@Part6 Practice on Passage
End
signals helpful
analogue
transmitted
modulation
achieve
frequency process
wave
on a radio
2009-7-27 P,18
End of this Unit
Unit 6
Telecommunication Technology
Chapter Three
&Part4 Extensive Reading@ Part 1 Notes to Text
@Part5 Notes to Passage& Part 2 Word Study
@Part3 Practice on Text @Part6 Practice on Passage
Chapter Study Tasks（ 3）
In this chapter,you will be able to
— Identify the key concepts of telecommunication
— Learn the basics of data and serial communications
— Get the general ideas of the text and the extensive reading
— Complete all the practice required
2009-7-27 P,2
@ Part 1 Notes to Text
1) In modern times,this process typically involves the
sending of electromagnetic waves by electronic
transmitters,but in earlier years it may have involved
the use of smoke signals,drums or semaphore,在现代，
这种传递的典型方式就是使用电子发射器发送电子波。而在较早的年代，传递方式可能用的是烟火讯号、击鼓声和旗语通讯法注释,注意 this process指代的是前文说的信号传递方式 ； 第二分句中的主语 it依然是指信号传递方式。
Key Concepts of Telecommunication
2009-7-27 P,3
2) Early inventors in the field include Alexander Bell,
Guglielmo Marconi and John Logie Baird,通信领域中的早期发明家有贝尔、马可尼和贝尔德。
注释,Bell,Alexander Graham，（ 1847-1922），美国发明家；
Guglielmo Marconi（ 1874— 1937），意大利物理学家； Baird，
John Logie，（ 1888-1946），英国电视发明家。
3) Telecommunication is an important part of the world
economy with the telecommunication industry's revenue being
placed at just under 3% of the gross world product,由于电信业的收入差不多占了世界总产值的 3%，所以电信是世界经济的一个重要部分。
注释,介词短语 with… 用作状语，表原因。现在分词短语 being
placed… 则是宾语补足语。
2009-7-27 P,4
4) This is to combat attenuation that can render the signal
indistinguishable from noise,这是为了防止信号衰减，而这种衰减则是由噪音导致的信号模糊。
注释,this指上文所说的必须要有一个放大器或转发器；不定式 to
combat attenuation是表语。
5） Alternatively,one could allocate each channel a recurring
segment of time over which to broadcast — this is known as
time-division multiplexing and is sometimes used in digital
communication,作为选择，你也可以给每个通道分配一个专门用来播放的循环时间段 — 这就是所谓的时分多址，这种技术有时候被用于数字通信。
注释,注意动词 allocate后面带的是双宾；短语 over which to
broadcast中的 which指代 a recurring segment of time。
End
2009-7-27 P,5 End
1,semaphore n,旗语通讯法 11.repeater n,转发器
2,gross n,总值 12.amplify v,放大,增强
3,analogue n,模拟 13.combat v,抗击 ; 防止
4,discrete adj,离散的 14.attenuation n,衰减
5,degrade v,降低 … 质量 15.render v,致使；造成
6,threshold n,极限 16.allocate v,分派,分配
7,intact adj,完整无缺的 17.recur v,循环
8,transceiver n.无线电收发机,收发器 18.segment n,段，节
9,router n,路由器 19.modulation n,调制
10,route v,发送 20.bluetooth n,蓝牙技术
& Part 2 Word Study
2009-7-27 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) ________________of signals
2) smoke______________
3) __________________networks
4) the gross________________
5) discrete________________
6) an analogue______________
transmission
signals
public telephone
world product
values
waveform
2009-7-27 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 may telecommunication have involved in early time?
b) Why do we say that telecommunication is an important part
of the world economy?
Task 2,Read,Write and Translate
It may have involved the use of signals,drums or semaphore.
Because the telecommunication industry's revenue is
placed at just under 3% of the gross world produc
A digital network may consists of one or more routers that route
data to the correct user,while an analogue network may consist
of one or more switches that establish a connection between
two or more users.
c) What is the difference between a digital networks and an
analogue network?
2009-7-27 P,8
( )1) Telecommunication is the transmission of signals over a
short time for the purpose of communication.
( )2) Telvevision,radio and telephone are devices that are used to
assist the process of widespreading telecommunication.
( )3) Telecommunication system mainly consists of a transmitter
and a transmission medium.
( )4) Digital signals are much better than analogue signals.
( )5) Both digital signals and analogue signals are disturbed by
noise when transmitted over a long distance.
Read and Judge
End
F
T
F
T
T
2009-7-27 P,9
Directions:Read the following short passage,Complete it by filling in the missing words.
A.receiver B,a phone line C,telecommunication D,between E,called
F,numerous G,because H,transmitter I,mobile J,systems
Consider a radio broadcast,In this case the broadcast tower is the
1)________,the radio is the 2)________and the transmission medium
is free space,Often telecommunication 3)________are two-way and a
single device acts as both a transmitter and receiver,or transceiver,
For example,a 4)________ phone is a transceiver.
Telecommunication over 5)________is called point-to-point
communication 6)________it is between one transmitter and one
receiver,7)________through radio broadcasts is
8)________broadcast communication because it is 9)________one
powerful transmitter and 10)________receivers
Read and Complete
End
H A
J
I
B
G
C
E D
F
2009-7-27 P,10
1) 她受到的良好教育培养了她精通英语的能力。（ shape）
2) 这一笔钱是用于贫困儿童的学费的 。 (allocate)
3) 中华民族是由汉族和其它五十六个少数民族构成的。 (consist of)
4) 昨天晚上台湾海峡的台风使海难再次发生 (recur) 。
5) 有很多政府高官涉嫌这次贿赂丑闻。 (involve)
Read and Translate
Directions:Put the following sentences into English,using the words or phrases given.
End
Very good education she recived has shaped her proficiency in
English.
This amount of money is allocated for the poor children’ s schooling.
The Chinese nationality consists of Han nationality and other
fifty-six minorities.
The typhoon in the Taiwan Straits made the wreck
recur yesterday evening.
Many highly-ranking government officers are involved
in the bribery scandal.
2009-7-27 P,11
Optical Fiber Cables
In practical fibers,the cladding(外层 )is usually coated with a
tough resin buffer layer(树脂保护层 ),which may be further
surrounded by a jacket layer(套层 ),usually plastic,These layers
add strength to the fiber but do not contribute to its optical(光的 )wave guide properties,Rigid(刚硬的 )fiber assemblies
sometimes put light-absorbing ("dark") glass between the
fibers,to prevent light that leaks out of one fiber from entering
another,This reduces cross-talk between the fibers,or reduces
flare in fiber bundle imaging applications.
For indoor applications,the jacketed fiber is generally
enclosed,with a bundle of flexible fibrous polymer(聚合物 )
strength embers like Aramid (e.g,Twaron or Kevlar),in a
lightweight plastic cover to form a simple cable,Each end of
the cable may be terminated with a specialized optical fiber
connector to allow it to be easily connected and disconnected
from transmitting and receiving equipment.
&Part4 Extensive Reading
2009-7-27 P,12
For use in more strenuous(艰辛的 )environments,a much more robust
cable construction is required,In loose-tube construction the fiber
is laid helically(螺旋形地 )into semi-rigid tubes,allowing the cable to
stretch without stretching the fiber itself,This protects the fiber
from tension during laying and due to temperature changes,
Alternatively the fiber may be embedded in a heavy polymer jacket,
commonly called "tight buffer" construction,These fiber units are
commonly bundled with additional steel strength members,again
with a helical twist to allow for stretching.
Another critical concern in cabling is to protect the fiber from
contamination(污染物 ) by water,because its component hydrogen
(hydronium) and hydroxyl(羟基 ) ions can diffuse(扩散 )into the fiber,
reducing the fiber's strength and increasing the optical attenuation,
Water is kept out of the cable by use of solid barriers such as
copper tubes,water-repellant jelly(防水胶 ),or more recently water
absorbing powder,surrounding the fiber.
2009-7-27 P,13
Finally,the cable may be armored(用装甲保护 )to protect it from
environmental hazards,such as construction work or gnawing
(咬,啃 ) animals,Undersea cables are more heavily armored in
their near-shore portions to protect them from boat anchors,
fishing gear,and even sharks,which may be attracted to the
electrical power signals that are carried to power amplifiers or
repeaters in the cable.
Modern fiber cables can contain up to a thousand fibers in a
single cable,so the performance of optical networks easily
accommodates even today's demands for bandwidth on a
point-to-point basis,However,unused point-to-point potential
bandwidth does not translate to operating profits,and it is
estimated that no more than 1% of the optical fiber buried in
recent years is actually 'lit'.
2009-7-27 P,14
Modern cables come in a wide variety of sheathings(护套 )and
armor,designed for applications such as direct burial in
trenches,dual use as power lines,installation in conduit(管道 ),
lashing to aerial telephone poles,submarine installation,or
insertion in paved streets,In recent years the cost of small
fiber-count pole mounted cables has greatly decreased due
to the high Japanese and South Korean demand for Fiber to
the Home (FTTH) installations.
End
2009-7-27 P,15
@Part5 Notes to Passage
1) In practical fibers,the cladding is usually coated with a tough
resin buffer layer,which may be further surrounded by a jacket
layer,usually plastic,实际上光纤的外层通常涂了一层坚韧的树脂保护层，树脂保护层或许还会再用一个套层包住，通常是塑料套层。
注释,介词短语 with a tough resin buffer layer 是方式状语，修饰谓语动词； which may be further surrounded by a jacket layer是非限制性定语从句，先行词是 a jacket layer。
2) Rigid fiber assemblies sometimes put light-absorbing ("dark")
glass between the fibers,to prevent light that leaks out of one
fiber from entering another.有时，坚硬的光纤装配将吸光（黑色）
玻璃介于光纤之间，这样才能防止光从一条光纤中渗漏入另一条光纤。
注释,不定式 to prevent light that leaks out of one fiber from
entering another既可用作目的状语，也可用作结果状语； that
leaks out of one fiber是定语从句，修饰 light。
2009-7-27 P,16 End
3) In loose-tube construction the fiber is laid helically into semi-
rigid tubes,allowing the cable to stretch without stretching
the fiber itself.在宽松管状结构中，光纤成螺旋形地被放入半坚硬的管道中，使电缆拉直，而不会拉直光纤。
注释,现在分词短语 allowing the cable to stretch without
stretching the fiber itself是伴随状语。
4) Undersea cables are more heavily armored in their near-shore
portions to protect them from boat anchors,fishing gear,and
even sharks,which may be attracted to the electrical power
signals that are carried to power amplifiers or repeaters in the
cable,海底电缆在靠海岸部分防护得更为坚实，以防止船锚，鱼具、
甚至可能是鲨鱼的侵害。这些东西都有可能被电能信号所吸引，这些信号在电缆中被传输给功率放大器或转发器。
注释,不定式短语 to protect them from boat anchors,fishing gear,
and even sharks是目的状语； which引导的是非限制性定语从句，
先行词是 boat anchors,fishing gear和 sharks。
2009-7-27 P,17
1.Listening Challenge
Spot Dictation
Directions,The following passage will be heard 3 times,During the second time,you
are required to put the missing words or phrases in the numbered blanks according to
what you hear,The third time is for you to check your answers,Now the passage
begins.
Modulation can also be used to transmit the information of
analogue 1)________ at higher frequencies,This is 2)________
because low-frequency 3)________ signals cannot be effectively
4)____________ over free space,Hence the information from a low-
frequency analogue signal must be superimposed on a higher-
frequency signal (known as a carrier wave) before transmission.
There are several different 5)_____________ schemes available to
6)________ this (two of the most basic being amplitude modulation
and 7)___________ modulation),An example of this 8)________ in
action is a DJ's voice being superimposed on a 96 MHz carrier
9)________ using frequency modulation (the voice would then be
received 10)__________ as the channel,96 FM” ).
@Part6 Practice on Passage
End
signals helpful
analogue
transmitted
modulation
achieve
frequency process
wave
on a radio
2009-7-27 P,18
End of this Unit
