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1. Laser Communication system
Prepared by :-
Saif Ansari
B.Tech 2nd year

2. Laser Communication System
• Laser communication is a system in which we send data using laser as
a carrier wave.
• Laser communication system works on the principle of “Amplitude
modulation” process.
• In this the amplitude of the carrier wave(laser) is varied according to
the instantaneous amplitude of modulating signal.

3. Block diagram
signal
Signal transmitter laser
Receiver
Signal

4. Transmitter
• It includes
• Signal processing circuit (ADC).
• Laser diode.
• Modulator.

5. Receiver
• It is a “Antenna” of the system.
• It includes
• Signal processing circuit (DAC).
• Detector (some kind of photodiode).

6. Example
• MCU-Multipoint control unit.
• UART – Universal asynchronous receiver/transmitter system.

7. Communication systems
• Optical cable communication.
• Free space optical communication.
• Laser communication in space.
• Wave guide

8. Laser in optical cable system.
• Fiber-optic cable has potential data rates of terabits per second.
• Fiber-optic cable is lighter, faster than copper cable.
• No EMI(electromagnetic interference) and doesn’t causes sparks.
• Laser can move vast quantities of data more securely than other
forms of communication.
• Fiber optics developed new technology WDM(wave division
multiplexing) that increases data rates by leaps and bounds.

9. Image for optical cable system

10. Free space optical communication
• It is a optical communication technology that uses laser light in free
space to wirelessly transmit data.
• Free space point to point optical links can be implemented using
infrared laser light.
• Current market demands
• In 2008, MRV communications introduced a FSO based system with a data
rate of 10gb/s having distance of 350m.
• In 2013, MOSTCOM started to serially produce a new FSO base system with a
data of up to 10gb/sec having distance 2.5km.

11. Image for free space optical communication

12. Laser communication in space
(artificial earth satellite transmission)
• For distances of millions of kilometers, artificial earth satellite
transmission is used.
• Current market demands
• In November 2001 he worlds first laser data connection was achieved by ESA
( European space agency) Artemis satellite with CNES earth observation
satellite.
• In November 2014, the first ever gigabyte laser based communication was
achieved by EDRS( European data relay system).
• Communication distance of 15 million miles( 24 million km)/tested.
• It also fades away the noise, distance, and other types of disruptions
interfering with the wave journey.

13. Image for laser communication in space

14. Wave guide
• Wave guide is a structure that guide waves.
• They enable a signal to propagate with minimal loss of energy by
restricting expansion to one dimension or two.