1. FREE SPACE OPTICSFREE SPACE OPTICS
A NEXT GENRATION WIRELESS COMMUNICATION
Presented By
B. Chandu AVINASH
G.V.P college of engg.M . Naga SRINIVAS
J.N.T.U KAKINADA

2. OVERVIEWOVERVIEW
 Deals with FSO – a latest communication technique
 Used in MAN’s
 Transmission through air
 Doesn’t involve optical fibers
 Uses INFRARED RAYS
 Doesn’t involve jamming
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3. CHALLENGECHALLENGE
ANDAND
IT’S SOLUTIONIT’S SOLUTION
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4. BASICSBASICS
Optical wireless
Different topologies
Involves transmission of data, voice and video
Many advantages when compared to fibers
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5. TOPOLOGIESTOPOLOGIES
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MESH POINT TO MULTI POINT
POINT TO POINT RING TOPOLOGY

6. IS FSO OPTICAL OR WIRELESS?IS FSO OPTICAL OR WIRELESS?
Shares some concepts of fiber optics
 wavelength’s 850nm to 1550 nm
 laser and amplifiers
Sending and receiving is done by OPTICAL-
ELECTRICAL-OPTICAL [O-E-O] presently
FSO can scale easily ultra bandwidth’s
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7. EDFAEDFA
EDFA-Erbium Doped Fiber Amplifier
A path way for high wavelengths and longer
distances
Less expenses for [O-E-O] conversion and
electrical amplification for each wavelength
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8. BANDWIDTH DRIVERS/TRENDSBANDWIDTH DRIVERS/TRENDS
Helps to attain high bandwidths
Telecommunication carriers implement FSO as
best access technology
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9. USAGE AND SPEED OF THE FSO AT VARIOUS APPLICATIONS 9

10. FEATURESFEATURES
FULLDUPLEX (bidirectional)
Uses lenses, optical wireless
unit, telescope for
transmission
 Very sensitive transmission
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11. DESIGN ISSUESDESIGN ISSUES
Apertures are used
Follows reflection,
refraction, diffraction,
combination of all
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12. TRANSMITTER APERTURETRANSMITTER APERTURE
Important aspects
Size
Quality
Size determines maximum eye safe laser
Quality with f-number tells us minimum
divergence
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13. RECIEVER APERTURERECIEVER APERTURE
Follows aperture size and f-number
Aperture size gives amount of collected data
f-number gives the detector field of view
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14. FSO SYSTEMSFSO SYSTEMS
 Doesn’t require any license
 Wavelength is about 1micrometer
 1 micrometer beam can translate into frequencies of
several hundred terahertz
 Better than the micro wave transmission (40gHz)
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15. FSO SYSTEMS(Contd…)FSO SYSTEMS(Contd…)
Divergence of 0.3 for distance of 1 KM
4mts diameter of beam
Those values are much more better than the
radial beams, micro beams
Since it works in free space it needs little
maintenance
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16. SECURITYSECURITY
 Transmission is not visible
to human eye
 Difficult for intruder to get
IR beam by direct method
since beam is small
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17. SECURITY(Contd…)SECURITY(Contd…)
 Transmission beam passes well
above the ground level
 It is impossible for an intruder
by indirect method by using
light photons since IR has low
power levels
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18. DRIVING FORCEDRIVING FORCE
Includes
Market driver
Economic driver
Service driver
Business driver
Environment driver
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19. APPLICATIONSAPPLICATIONS
Metro network extensions
to connect to new networks
Enterprise
LAN-LAN connectivity
Enterprise applications
Point to multipoint
Fiber complement
As redundant link
DWDM Services
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20. CHALLENGESCHALLENGES
Physical obstructions
Building seismic activity
Scintillation
Absorption
Beam wander
Beam spreading
Safety
Human exposure to laser
High voltages
Weather Severity
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21. EFFECT OF ATMOSPHEREEFFECT OF ATMOSPHERE
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22. CONCLUSIONCONCLUSION
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FSO allows us to provide optical connectivity cost
effectively, quickly, reliably and is a most secured
data transmission technology.

23. REFERENCESREFERENCES
 Mendelson , James S. and Dorrier , Charles R. “Free Space Optics:
Fixed Wireless Broadband”
 White, Chad “How to Squeeze More Data Over What’s Already
There ”
 www.laseroptronics.com
 www.ieee.org
 www.science tech.com
 www.efymag.com
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24. ANY QUERIES?ANY QUERIES?
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25. THANK YOUTHANK YOU
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