Fiber Optics

1
Fiber Optics

• COMM 2500
• Tim Larson

2
What are fiber optics? Fiber optic
communications is different from any other data
transmission method Does not use electricity
through a conductor to transmit information.
Instead of electrical signals, modulated light
is used to quickly transmit data over long
distances through an insulated glass
fiber-type material. Currently the best long
distance communications method because it
provides much faster data transfer speeds when
compared to traditional interconnection media
such as copper wire.
3
Benefits of fiber optics over conventional copper
or coaxial cable?
Higher tensile strength Lower mass and
smaller size Maximizes wiring conduit usage
while minimizing installation problems
Does not carry electricity, so they are ideal
for volatile environments where a
spark from a conventional broken copper
line could cause an explosion. Will not
corrode like copper or aluminum Not
susceptible to EMI, thus carry a better signal
Signals do not degrade as quickly Easily
expandable to all more equipment and people
to join a network.
4
Fiber Optic Cable
Composed of glass, silica fiber, or plastic.
Silica fiber used for high power
applications Plastic reserved for isolation of
sensitive systems from high voltages Specialt
y glass fibers used to send data streams over
long distances Comprised of several
layers Glass fiber Buffer region Strength
member PVC outer jacket
5
Glass Fiber
Buffer Region

Strength member
PVC Outer Jacket
Fiber Optic Cable
6
Optical Fibers
Hair-thin solid strands of high quality glass,
which are combined to form cables for
transmitting information via light pulses from
one point to another. Two basic types of
optical fiber used for communications
Multimode fiber Multimode fiber has a
larger core (area where light travels),
carries less information and is more expensive
than single-mode fiber.Typically used in
campus and inside building (premises)
applications primarily because of the low cost of
the devices (LEDs), connectors, and overall
termination cost. Single-mode fiber.
Single-mode fiber, because of its very high
bandwidth, is used in long distance trunk
lines (cable between cities) and fiber-to-the
curb (fiber from the central office to the curb
/ pedestal in front of a home or office
building) applications.
7
Wavelength Division Multiplexing(WDM)Fibe
r optic wavelength division multiplexers are
passive devices that combine light signals with
different wavelengths, onto a single fiber.
8
Applications
LAN Local Area Network (industrial, inside
buildings) WAN Wide Area Network (around towns
and cities) MAN Metropolitan Area
Network FTTD Fiber-to-the Desk (short
distances) FTTC Fiber-to- the-Curb (high
bandwidth to outside the home) FTTH
Fiber-to-the-home (high bandwidth inside the
home)