Introduction to Free space Optics and Applications.

1. Free Space Optical Communication
(FSO)
Supervised by:
Prof. Magdy Ibrahim
Prepared by:
Ahmed Ashraf Abdel-Haseb
Ahmed-Houssam Mahmoud
Ahmed Magdy El-Sayed
Amr Atef Hussein
Mohamed Khaled Abo-Seif

2. Free Space Optical Communication
(FSO)
Supervised by:
Prof. Magdy Ibrahim
Prepared by:
Ahmed Ashraf Abdel-Haseb
Ahmed-Houssam Mahmoud
Ahmed Magdy El-Sayed
Amr Atef Hussein
Mohamed Khaled Abo-Seif

3. Outlines
• Introduction [1]
• Free Space Optical Link Design [2]
• Applications [3]
• FSO vs. Fiber vs. Microwave Links

4. Outlines
• Introduction [1]
• Free Space Optical Link Design [2]
• Applications [3]
• FSO vs. Fiber vs. Microwave Links

5. Introduction
• Operation of FSO
• Uses
• Advantages and Disadvantages
• Security Aspects
• Safety Aspects

6. Introduction
• Operation of FSO
• Uses
• Advantages and Disadvantages
• Security Aspects
• Safety Aspects

7. Introduction
• Operation of FSO
• Uses
• To cross a public road or other barriers which the sender and
receiver do not own.
• For communications between spacecraft.
• Speedy service delivery of high-bandwidth access to optical
fiber networks.
• Advantages and Disadvantages
• Security Aspects
• Safety Aspects

8. Introduction
• Operation of FSO
• Uses
• Advantages and Disadvantages
 Advantages
• License-free operation.
• High bit rates.
• Low bit error rates.
• Immunity to electromagnetic interference.
• Security.
• Easiness and speed of installation.
• Security Aspects
• Safety Aspects

9. Introduction
• Operation of FSO
• Uses
• Advantages and Disadvantages
 Disadvantages
• Beam dispersion.
• Atmospheric absorption.
• Rain, Snow, Fog (10..~100 dB/km attenuation).
• Background light.
• Security Aspects
• Safety Aspects

10. Introduction
• Operation of FSO
• Uses
• Advantages and Disadvantages
• Security Aspects
• Safety Aspects

11. Introduction
• Operation of FSO
• Applications
• Advantages and Disadvantages
• Security Aspects
• Safety Aspects
• Eye Damage

12. Outlines
• Introduction [1]
• Free Space Optical Link Design [2]
• Applications [3]
• FSO vs. Fiber vs. Microwave Links

13. Free Space Optical Link Design
• FSO Subsystems
• FSO Link Equation and Link Budget
• Theoretical Range Limit
• BER, Data Rate, and Range

14. Free Space Optical Link Design
• FSO Subsystems
1. Transmitter
2. Receiver
3. Tracking System
• FSO Link Equation and Link Budget
• Theoretical Range Limit
• BER, Data Rate, and Range

16. Free Space Optical Link Design
• FSO Subsystems
1. Transmitter
2. Receiver
3. Tracking System
• Requirements:
Tracking Frequency, Resolution, Speed, … etc.
• FSO Link Equation and Link Budget
• Theoretical Range Limit
• BER, Data Rate, and Range

17. Free Space Optical Link Design

18. Free Space Optical Link Design

20. Free Space Optical Link Design
• FSO Subsystems
• FSO Link Equation and Link Budget
• Theoretical Range Limit
• BER, Data Rate, and Range
.

23. Outlines
• Introduction [1]
• Free Space Optical Link Design [2]
• Applications [3]
• FSO vs. Fiber vs. Microwave Links

24. Applications
Free Space Optical Networks
• Point to Point FSO Systems
• Mesh FSO Systems
FSO on HAPs (Future Application)

25. Applications
Free Space Optical Networks
• Point to Point FSO Systems
• Mesh FSO Systems
FSO on HAPs (Future Application)

26. Applications
3 A receiver at the other end of
2 Transmitter projects the the link collects the light using
carefully aimed light pulses
lenses and/or mirrors
into the air
5 Reverse direction data
transported the same way.
• Full duplex
1 Network traffic 4 Received signal
converted into converted back into
pulses of fiber or copper and
invisible light connected to the
representing 1’s network
and 0’s
Anything that can be done in fiber
can be done with FSO

27. Applications
Free Space Optical Networks
• Point to Point FSO Systems
Disadvantages
• Cannot connect more than 2 points
• The points cannot have arbitrary distance between them
• Has the poorest network and traffic protection
• Mesh FSO Systems
FSO on HAPs (Future Application)

28. Applications
Free Space Optical Networks
• Ring FSO Systems
• Mesh FSO Systems
FSO on HAPs (Future Application)

29. Nodes of a mesh - FSO topology on fl at terrain but with nodes at different heights.

30. Applications
Free Space Optical Networks
• Ring FSO Systems
• Mesh FSO Systems
Advantages
• The best network and service protection
• Very high data rates
• Scalability and expandability
FSO on HAPs (Future Application)

31. Applications
Free Space Optical Networks
• Ring FSO Systems
• Mesh FSO Systems
Disadvantages
• The complexity of each node in the mesh topology.
• High Cost
FSO on HAPs (Future Application)

32. Nodes over a geographical territory with line of sight between them.

33. Applications
Free Space Optical Networks
• Ring FSO Systems
• Mesh FSO Systems
FSO on HAPs (Future Application)
• Use on high altitude platforms (HAPs), (20 – 30 Km).
• Estimated Range: more than 600km.
• .

35. Applications
Free Space Optical Networks
• Ring FSO Systems
• Mesh FSO Systems
FSO on HAPs (Future Application)
Advantages:
• Stratospheric Conditions.
• Low attenuation, no cloud interference, low tempreture…etc.
• Cost Effective (Compared to Satellites)
• FSO Advantages
• High Data rate, Low Power Consumption …etc.
• .

36. Outlines
• Introduction [1]
• Free Space Optical Link Design [2]
• Applications [3]
• FSO vs. Fiber vs. Microwave Links

37. FSO vs. Fiber vs. Microwave Links
Criteria FSO Optical Fiber Microwave
Data rate Up to 10 Gbps 100 Mbps to 100 Gbps 275 Mbps
Installation Easy Difficult Moderate
Cost Moderate High Moderate
Maintenance low High low
Most common Between buildings Point-to point Point-to-point
uses
Short distance Long distance Short distance
Advantages Price Security speed
performance capacity and speed
No license Immunity to EMI
Disadvantages Can be intercepted Difficult to splice Can be intercepted
determinate Requires radio license
Security Moderate Excellent Poor

38. References
[1] S.V. Kartalopoulos , “ Disaster Avoidance in the Manhattan
Fiber Distributed Data Interface Network , ” Globecom ’
93, Houston, TX, December 2, 1993 .
[2] Scott Bloom, “The Physics of Free Space Optics”, AirFiber, Inc.
[3] “Free-Space Optical Communications on
HAPs”, www.hapcos.org , accessed on : 13-May-2012

39. Thanks