Laser Communication

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Laser Communication

• Bryan J Steward

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What Is Laser Communication?
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Free Space Laser Communication

• Transmitting information via a laser beam
• Sound
• Video
• Data
• Terrestrial / Space based systems

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How Does it Work?
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What is the Transmitter?

• The transmitter involves
• Signal processing electronics (analog/digital)
• Laser modulator
• Laser (visible, near visible wavelengths)
• CO2
• Nd
• GaAlAs
• many others

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What is the Receiver?

• The receiver involves
• Telescope (referred to as antenna)
• Detector
• Signal processor

• Often both ends will be equipped
• with a receiver and transmitter

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Why Laser Communication?

• Current high speed communications technology
• Radio
• Fiber Optics

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Why not RF?

• Bandwidth
• LC 100 times greater than RF
• Power
• All power directed at target, so much less
  transmission power required
• Size / Weight
• LC antenna much smaller than RF

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Why not Fiber Optics?

• Not always possible to lay fiber lines
• Satellites
• Combat zones
• Physically / Economically not practical
• Emergencies
• LC being incorporated into fiber optic networks
  when fiber not practical

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Current Applications

• Livermore, CA
• 28 km
• 2.5 Gbps
• 1600 T1 lines
• 400 TV channels
• 40,000 phone conversations
• NASA
• Satellite - satellite
• Earth - satellite

earth
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Questions?

• orms8_at_hotmail.com