JLD College of Engineering &
LASER TORCH BASED VOICE
SOURAV DAS - D16005400633008
ARIJIT SIKDER - D16005400633002
MITALI MONDAL - D16005400633011
Our final year project is based on the concept of laser (Light Amplification by
Stimulated Emission of Radiation) for transmitting analog signals. We have used
phototransistor to receive the signal at receiver. Laser as a communication medium
can provide a good substitute for the present day. Laser communications offers a
viable alternative to RF Communications for inter satellite links and other
applications where high performance links are a necessity. High data rate, small
antenna size, narrow beam divergence, and a narrow field of view are characteristics
of laser communications that offer a number of potential advantages for system
design. For voice transmission amplitude modulation of laser pulse was used to
transmit the voice signal. Condenser microphone (acts as a transducer) converts the
voice into electric pulse which was then amplified and transmitted through laser.
Photo detector at receiver detects the laser light and voice output through loud
OBJECTIVES OF PROJECT
The main aim of this paper is to construct a Laser communication system by
using low cost laser torch and available electronic equipment which can be got
easily form local electronics shop everywhere and people can construct for
their personal use.
• To implement light based voice transmission and reception system by using
light from a Laser-torch as the carrier of the signal.
• To reduce the complexity for communication in the places where optical
fiber or any wired communication is very difficult and expensive.
APPLICATION OF PROJECT
1. Using this circuit we can communicate with our neighbors wirelessly.
2. It can be used in inaccessible areas.
3. In future it can be commissioned in satellites for communication.
4. It can be used in conference halls.
1.The factors such as beam dispersion, background light, shadowing, rain, fog,
snow, pollution, smog causes an attenuated received signal and lead to higher
bit error rates.
2. Limited up to the range of 500m.
3. For longer distance communication high power laser is required which is
1. Multiple voice, data, picture, video can be multiplied simultaneously to
perform communication using Multiplexer.
2. Half duplex or even full duplex communication can be achieved by software
3. A more power laser can be used to increase the range of communication.
4. Laser can be replaced by IR laser that can’t be visible by bare eye.