i m student of environmental science

1. COMMUNICATION
CHANNEL
Maryam
2486

2. COMMUNICATION CHANNEL
• WHAT IS COMMUNICATION
CHANNEL ?
A path through which information is
transmitted from one place to
another known as communication
channel or medium.
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3. COMMUNICATION CHANNEL
TYPES OF COMMUNICATION
MEDIA
GUIDED MEDIA
 UNGUIDED MEDIA
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4. TYPES
GUIDED MEDIA
• Transmission of
broadcasted
information within
physical boundary
• Example :
Fiber optics, twisted
pair cable, coaxial
cable
UNGUIDED MEDIA
• Data transmission
through air
• It is also referred as
wireless
• Example :
Microwave, radio
communication
satellite etc
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5. DIFFERENCE
• GUIDED MEDIA
 Bounded media
 Physical media
 Data transmission
through cabling
media
 Specific path of data
signals
UNGUIDED MEDIA
 Unbounded media
 Wireless
 Data transmission
through air
 No specific path of
data signals
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6. GUIDED MEDIA
fig :Coaxial cable fig :Twisted pair cable
fig :Fiber optic
cables
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7. COAXIAL CABLE
Fig :layers surround the inner
conductor
Long distance
transmission
Center wire surrounded
by insulation
Inner conductor
surrounded by 3 layers
80 times greater
bandwidth then twisted
pair
Used in T.V
cables,LAN,telephone
lines
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8. TWISTED PAIR
CABLE
Two wires twisted
around each other
Insulating copper wire
Less bandwidth than
other
Twisting reduce
electromagnetic
interference
Two types of cables
Shielded twisted pair
Unshielded twisted pair
cable
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9. TYPES
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10. FIBER OPTICS
CABLE
Glass fibers
Layer of core and
cladding
Refractive index
Data transmission
through light waves
An insulating layer
Plastic jacket
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11. UNGUIDED
MEDIA
Fig : satellite
Fig: microwave system
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12. MICROWAVES
Wavelength beyond
the visible and radio
waves
High towers
Distance b/w towers is
30 miles
Wide bandwidth
No wiring required
Used by mobile
companies
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13. COMMUNICATION
SATELLITE
Earth station send signals
Space station receive
signals
Signals retransmitted to
earth station
Signals microwave form
High speed of data
transmission
Broadcasting, mobile
phones ,weather tracking
etc
Expensive installation
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14. RADIO WAVES
• Radio is transmission of radio signals at
less than frequency of visible light
• Directed Waves
• Noise Concurrency
• Radio Wave's Directness
• Unlimited Range
• Interference
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