TOPIC 7 – Media, Antennas and Propagation
7.1. Media

What is it?

How Media Fits into the Network

Media Types

When are different media used?
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TOPIC 7 – Media, Antennas and Propagation
7.1. Media – Network Components
1
Telecommunications
Processors
2
3
2
5
Telecommunications
Telecommunications
Software
Software
PCs, NCs,
and Other
Terminals
Media
Courtesy of Byungioon Yoo
4 Computers
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TOPIC 7 – Media, Antennas and Propagation
7.1. Media

Media is the means by which signals are transmitted.

Media is one component of a communications
system.

Types of Media:
 Wire
 Cable
 Coaxial Cable
 Fiber Optic Cable
 Wireless
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TOPIC 7 – Media, Antennas and Propagation
7.1. Media - Bandwidth
 Twisted pair
 May be shielded or not
 Analog bandwidth 1 MHZ
 Coaxial cable
 Better noise shielding, 50-750 MHz
 Existing infrastructure
 Fiber optic cable
 Uses light
 Unidirectional
 More secure, very low attenuation and noise
 Very high Capacity
 Expensive
Courtesy of Byungioon Yoo
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TOPIC 7 – Media, Antennas and Propagation
7.1. Media – Wire and Cable
Critical Parameters
 Is it signal or power rated?

What is the current or power capacity?

If it’s signal rated, what is the bandwidth?

How is it shielded?

How is it insulated?
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TOPIC 7 – Media, Antennas and Propagation
7.1. Media - Copper Wire
Wire current handling capacity values
Area
Resistivity
Sq. mm
mhos/m
6
3.0
10
1.8
16
1.1
25
0.73
35
0.52
50
0.38
70
0.27
Current
Amps
55
76
105
140
173
205
265
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TOPIC 7 – Media, Antennas and Propagation
7.1. Media - Copper Wire
American Wire Gauge (AWG) Table
1 AWG is 289.3 thousandths of an inch
 2 AWG is 257.6 thousandths of an inch
 5 AWG is 181.9 thousandths of an inch
 10 AWG is 101.9 thousandths of an inch
 20 AWG is 32.0 thousandths of an inch
 30 AWG is 10.0 thousandths of an inch
 40 AWG is 3.1 thousandths of an inch
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TOPIC 7 – Media, Antennas and Propagation
7.1. Media – Twisted Pair Copper Wire
Definition:
 Consists of one or more pair of wires twisted together.
 There are different types of twisted pair cable and have
different electrical properties.
 Factors that affect those properties include the number
of twists per foot of each pair, the number of twists per
foot for multiple pairs twisted together, the diameter as
gauge of the wire and the type of insulation.
 Commonly two primary types are used: shielded and
unshielded.
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TOPIC 7 – Media, Antennas and Propagation
7.1. Media – Twisted Pair Copper Wire
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TOPIC 7 – Media, Antennas and Propagation
7.1. Media – Twisted Pair Copper Wire
 Shielded Twisted Pair (STP)
 Definition: STP is surrounded by a foil or braid jacket
to protect the internal wires from external electrical
interference.
 Pros & Cons
Easy to Install
Wire Easy to Route and Use
Support Higher Data Transmission than UTP
Less Vulnerable to Electrical Interference than UTP
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TOPIC 7 – Media, Antennas and Propagation
7.1. Media – Twisted Pair Copper Wire
Unshielded Twisted Pair (UTP)
 Definition: consists of one or more twisted pairs of copper
wire encased in a common insulated jacket. The wires are
insulated from each other and twisted together within another
insulating sheath.
 Pros & Cons
 Already Installed in many buildings.
 Inexpensive.
 Can be used for voice and data communication.
 Supports many LAN's Systems.
 Small data rate.
 Limited length of run (attenuation Max. 328 feet).
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 Vulnerable to interference.

TOPIC 7 – Media, Antennas and Propagation
7.1 Media - Cable
Copper cabling comes in three basic varieties
 CMG: General Purpose
 Patch cables for instance
 PVC insulation and PVC jacket are normal
 CMR: Riser Rated
 For building riser shaft. “Vertical Cabling” between floors
 Various insulation, and PVC jacket
 CMP: Plenum Rated
 Use anywhere you are running in environmental air
 Under raised floors, above the ceiling, in riser shafts
 FEP insulation and PVC jacket are normal
 Best combustion resistance of these three types
Courtesy of Intel
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TOPIC 7 – Media, Antennas and Propagation
7.1. Media - Cable Uses

Dormitories:
 reduces fire fuel loading
 produces 17x less smoke
 improves available “time to exit”
 difference between safety and injury, or injury
and death

Computer Rooms:
 dramatic reduction in smoke and fuel loads
 no PVC-induced acid to corrode computer parts
Courtesy of Intel
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TOPIC 7 – Media, Antennas and Propagation
7.1. Media - Cable Comparison
Criteria
CMP
CMP-50
Max Temp Rating
60-75 C
200 C
Insulation Material
FEP (e.g. Teflon)
FEP (e.g. Teflon)
Jacket Material
PVC
FEP (e.g. Teflon)
Smoke Creation
-
17x less than CMP
Fuel Load
-
3x to 5x less than
CMP
Courtesy of Intel
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TOPIC 7 – Media, Antennas and Propagation
7.1. Media – Coaxial Cable
•What’s different about it electrically?
•What’s different about it physically?
•How is it used?
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TOPIC 7 – Media, Antennas and Propagation
7.1. Media – Coaxial Cable
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TOPIC 7 – Media, Antennas and Propagation
7.1. Media – Coaxial Cable
Courtesy of Belden
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TOPIC 7 – Media, Antennas and Propagation
7.1. Media – Coaxial Cable
Courtesy of Belden
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TOPIC 7 – Media, Antennas and Propagation
7.1. Media – Coaxial Cable
Courtesy of Belden
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TOPIC 7 – Media, Antennas and Propagation
7.1. Media – Coaxial Cable
Courtesy of Belden
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TOPIC 7 – Media, Antennas and Propagation
7.1. Media – Coaxial Cable
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TOPIC 7 – Media, Antennas and Propagation
7.1. Media – Coaxial Cable
Courtesy of Belden
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TOPIC 7 – Media, Antennas and Propagation
7.1. Media - Coaxial Cable
External Cover
Braided Wire
High
Signal
Wire
Insulation
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© The McGraw-Hill Companies, Inc., 1997
TOPIC 7 – Media, Antennas and Propagation
7.1. Media – Coaxial Cable
Courtesy of Belden
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TOPIC 7 – Media, Antennas and Propagation
7.1. Media – Coaxial Cable
Courtesy of Belden
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TOPIC 7 – Media, Antennas and Propagation
7.1. Media – Coaxial Cable
Courtesy of Belden
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TOPIC 7 – Media, Antennas and Propagation
7.1. Media – Coaxial Cable
VSWR- Voltage Standing Wave Ratio
Courtesy of Belden
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TOPIC 7 – Media, Antennas and Propagation
7.1. Media – Fiber Optic Cable
•What’s different about it electrically?
•What’s different about it physically?
•How is it used?
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TOPIC 7 – Media, Antennas and Propagation
7.1. Media – Fiber Optic Cable - Characteristics
Made of hair-thin strands of glass.
 Transmits generated light impulses.
 Pulses of light, rather than electrons, represent data.
 Sends information much faster than existing copper-based cable
 Carries considerably more information
 Superior transmission quality less maintenance.
 Immune to electronic interference.
 Low attenuation over long distances
 Repeaters (amplifiers) can be used to extend transmission distances.
 Can transmit 24,000 telephone calls at the same time.
 It carries 150 times the capacity of bundle of copper cable.

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TOPIC 7 – Media, Antennas and Propagation
7.1. Media – Fiber Optic Cable - Construction
Courtesy Black Box
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TOPIC 7 – Media, Antennas and Propagation
7.1. Fiber Optic Cable - Transmission
Protective Coating (Jacket)
Glass Cladding
Glass Core
Protective Coating
Glass Cladding
© The McGraw-Hill Companies, Inc., 1997
Glass Core
Coherent Light Beam 31
OPIC 7 – Media, Antennas and Propagation
.1. Media – Fiber Optic Cable - Transmission
OPIC 7 – Media, Antennas and Propagation
7.1. Media – Fiber Optic Cable - Transmission
OPIC 7 – Media, Antennas and Propagation
7.1. Media – Fiber Optic Cable - Transmission
OPIC 7 – Media, Antennas and Propagation
7.1. Media – Fiber Optic Cable - Transmission
OPIC 7 – Media, Antennas and Propagation
7.1. Media – Fiber Optic Cable Single Mode
OPIC 7 – Media, Antennas and Propagation
7.1. Media – Fiber Optic Cable Transmission
OPIC 7 – Media, Antennas and Propagation
7.1. Media – Fiber Optic Cable - Multimode
OPIC 7 – Media, Antennas and Propagation
. Media – Fiber Optics - Multimode Fiber
easons to Use Multimode Fiber
Not aligning fiber optic cable properly will create
multiple resonance modes.
Aligning single mode cable is much more difficult than
aligning multi mode cable.
Single mode cable is intolerant of handling multiple
resonances
Multimode cable allows the propagation of these
multiple resonances.
Since it is simpler to install, labor costs for multimode
instillations can be reduced as much as 25-40%.
OPIC 7 – Media, Antennas and Propagation
Media – Sample Fiber Optic Transmission System
OPIC 7 – Media, Antennas and Propagation
.1. Media – Fiber Optic Cable Connectors
OPIC 7 – Media, Antennas and Propagation
.1. Media – Fiber Optic - Modulation
OPIC 7 – Media, Antennas and Propagation
1 Media – Fiber Optics & Coax
Hybrid Fiber/Coax (HFC)
 Use fiber optic cable from the station to the
neighborhood and Coax to the home
 Cheaper alternative uses existing equipment
Fiber to the curb or home (FTTC)
 Use fiber all the way to the home
 The added expense may justify the cost depending
on the usage.
OPIC 7 – Media, Antennas and Propagation
1 Media – Fiber Optics & Coax
Comparison Chart of POF, glass optical fiber, and copper wire.
OPIC 7 – Media, Antennas and Propagation
1 Media – Fiber Optics & Coax
OPIC 7 – Media, Antennas and Propagation
1 Media – Fiber Optics & Coax
The Communications Spectrum
AM 550K-1650KHz
LF
TV (VHF) 54M-216Mhz
FM 88M-108MHz
TV (UHF) 220M-500MHz
LF
10K
MF
HF
100K 1M
VHF UHF Microwave Optical
10G
100M 1G
10M
Cordless 34, 900MHz
PCS 1.85-2.2GHz
Cellular 800MHz
OPIC 7 – Media, Antennas and Propagation
. Media - Network Components
rk Component
Media
rocessors
Software
Channels
Topology/
chitecture
rchitecture
Examples
Twisted-pair wire, coaxial cable, fiber optics,
microwave radio, communications satellites, cellular
phone systems, radio, infrared
Modems, multiplexers, switches, routers, hubs,
gateways
Network operating systems, telecommunications
monitors, middleware
Analog/digital switched/nonswitched,
circuit/message/packet/cell switching, bandwidth
alternatives
LAN, WAN, VAN, VPN, Client-Server, Internetworked
Enterprise
PIC 7 – Media, Antennas and Propagation
Media - Alternatives
Twisted
TwistedPair
Pair
Coaxial
Coaxial
Fiber
FiberOptic
Optic
Hybrid
Hybrid Fiber/Coax
Fiber/Coax (HFC)
(HFC)
ifferent
Different
edia for
Media
for
elecommunications
elecommunications
Fiber
Fiber to
to the
the Curb
Curb (FTTC)
(FTTC)
Radio
Radio
Cellular
Cellular Radio
Radio
OPIC 7 – Media, Antennas and Propagation
7.1. Media - Cable- Improved Safety
Limited Combustible Cable (CMP-50)
 Designed to meet requirements of NFPA
 Significantly reduced fuel and smoke loading
 Similar to ceiling tile and wallboard in fire resistance
properties
 Does not replace standard CMP plenum cable
 It is an alternative, with better smoke/fire properties
 Listing in place with UL
 Europe and Canada have similar requirements in the
works, though US is still more stringent
pic 7 Media, Antennas and Propagation
. Media – Cable - PVC
cabling Issues
 Toxic Use Reduction Institute (TURI) (UMass, Lowell)
 Published report on toxins in Wire and Cable products (April
2002)
 PVC in coated wire and cable is different than “regular” PVC
 PVC is treated with plasticizers to coat cables.
 Plasticizer of choice is phthalates
 PVC is treated with stabilizers to slow decomposition
 Stabilizer of choice is lead
 Plus flame-retardants and other additives (including
cadmium, chromium, antimony, halogens, etc)
PIC 7 – Media, Antennas and Propagation
Media – Cable - More Problems with PVC
VC has dioxin byproducts in many stages of it’s life
isposal of PVC is not currently a large issue
 PVC is the liner for most landfills
 But PVC for cabling includes lots of additive chemicals
 Incineration releases hydrogen chloride gas and heavy metals
 Incineration of wire/cable has already been banned in Europe
 Additive products in PVC wire/cable can leach into groundwater
 Shredding the cable results in EPA labeling the “fluff” as
hazardous waste
 California Prop 65 (1986) includes all these chemicals already
ndoor Air Quality
 Miles of this stuff in your environmental air spaces
 Known carcinogens, known respiratory irritants
OPIC 7 – Media, Antennas and Propagation
7.1. Media – Fiber Optic Cable - Construction
OPIC 7 – Media, Antennas and Propagation
1. Media – Fiber Optic Cable – Cross Section