16-08-2014, 01:33 PM
SEMINAR REPORT ON LASER COMMUNICATION SYSTEM
[attachment=66668]
ABSTRACT
Laser communication is one of the key area in wireless Communications.
This paper includes analysis, optimization, design and system level development of
signal transformation between satellites or any two sources. Which work similarly to
fiber optic links, except the beam is transmitted through free space. While the
transmitter and receiver must require line-of-sight conditions, they have the benefit of
eliminating the need for broadcast rights and buried cables. Laser communications
systems can be easily deployed since they are inexpensive, small, low power and do not
require any radio interference studies. The carrier used for the transmission signal is
typically generated by a laser diode. Two parallel beams are needed, one for
transmission and one for reception.
INTRUDUCTION
Laser Communication is one of the emerging area of wireless communication
system. Due to its low noise ratio makes its one of the well suited communication
medium for exchange of information. Currently laser commutation is adopted in satellite
communication for space research activities and due to its efficiency on low noise ratio,
inexpensive , low power and its flexibility and its resistance to the radio interferences
makes laser communication as one of research area in wireless communication. In this
process, this paper comprises the one such application of laser communication for
information exchange between any two devices.
In Laser Communication the transmitter and receiver must require a line-of-sight
conditions and Laser communications systems have the benefit of eliminating the need
for broadcast rights and buried cables. The carrier used for the transmission signal is
typically generated by a laser diode. Two parallel beams are needed, one for
transmission and one for reception.
Laser communications systems are wireless connection through the atmosphere.
Which is focused on decreasing the noise ratio in optical communication system. Laser
communications systems work similarly to fiber optic links, except the beam is
transmitted through free space. In Laser Communication the transmitter and receiver
must require a line-of-sight conditions and Laser communications systems have the
benefit of eliminating the need for broadcast rights and buried cables.
IMPLEMENTATION
The voltage variation on the solar panel is amplified by a low-voltage audio
power amplifier LM386 and reproduced by a speaker. The maximum output of
audio amplifier LM386 is 1 watt, while its voltage gain is 20 to 200. The circuit consists
of a transmitter and a receiver. Both the transmitter and the receiver are built around IC
LM386, powered by a 9V battery.
Fig. 1 shows the transmitter circuit Here a laser diode (LD1) with maximum
operating voltage of around 2.6V DC and maximum operating current of 45 mA is
used to transmit the audio signal. The voltage divider network formed by R2, R3 and
VR3 keeps the voltage as well as the current for the laser diode in the safe region. In
place of the laser diode, you can also use a laser pointer. Remove the battery from the
laser pointer. Extend two wires from terminals of LD1 and connect them to the battery
terminals of laser pointer. The spring inside the laser pointer is the negative terminal.
The output power of the laser pointer is 5 mW. Take care while working with laser, as
direct exposure to the laser beam can be hazardous to your eyes. Point the laser beam to
the solar panel. Potmeter VR1 (10-kilo-ohm) is used to change the level of the input
audio signal. The audio input (Vin) is taken from the preamplifier output of the music
system (CD player, DVD player, etc). Capacitor C2 and preset VR2 are used to vary the
gain of the LM386.
Fig. 2 shows the receiver circuit. The audio signal transmitted by the laser
diode (LD1) is received by the calculator’s solar panel and amplified by IC2. The gain
of the amplifier is fixed by capacitor C7. Preset VR4 is used to change the signal level
WORKING
Microphone Amplifier: The first step in transmitting sound is to digitize sound
waves. For this we used an electric microphone. The microphone he sold us had three
leads, which after considerable angst we decided were for power, ground, and signal.
The signal coming off the mic was far too low to be read (with any degree of precision)by the analog to digital converter. For that we are using the LM386 op-amp to increase
the power and signal. Before the signal is put through the amplifier, first put the signal
through a capacitor to remove DC, and then through a voltage divider to appropriately
bias the signal. The gain is adjusted by the resistors and for the microphone the gain is
around 50-100 (depending on how much popping and how much quality you want).
UART ( universal asynchronous receiver/transmitter) : It is a piece
of computer hardware that translates data between p
ADVANTAGES
The advantages of laser communication is that it allows very fast communication
service between two or more devices than other modes of communications.
ìì) It can provide speed more than 1GBps.So it overtakes the LAN or wireless LAN
comprehensively.
Ììì) Laser communications systems have the benefit of eliminating the need for broadcast
rights and buried cables.
Ìν) Laser communications systems can be easily deployed since they are inexpensive,
small, low power and do not require any radio interference studies. The carrier used for
the transmission signal is typically generated by a laser diode. Two parallel beams are
needed, one for transmission and one for reception.
ν) The transmitting and receiving station are smaller and lighter for given range. Less
overall power is required for the given distance and data rate. Higher data rate may be
achieved for given distance and power output.
νì) A tiny light detector may allow for superfast broadband communication over
interplanetary distances. This technology advance offers the space laser communication
system designer the flexibility to design very lightweight, high bandwidth, low-cost
communication payloads for satellites whose launch costs are a very strong function of
launch weigh.
νìì) Signals can be reproduced without distortion, even long distances. So the system
could be use for communication and cable television transmission.
ί ) A one way laser communications system that is capable of the transmission of both ẋ
text and sound.
νί)even by a minute fraction of a degree, the laser will miss by thousands of miles.
Instead of better and faster pictures, there could be no pictures.
The noise in photodiodes The main sources of noise are dark current noise, shot noise
and thermal noise in a photodiode. There is one more source of noise due to random
nature of the avalanche in an APD. The dark current noise arises due to dark current
which flows in the circuit when th
Conclusion
This is new wireless technology to transmit the data or sound signal from one section
to other section through the laser beam of the system. This system is safety and without
radiation. so it is not harm to living beings. The system can likely transmit data and
sound much faster than the other system(like 1GB/s). because of this laser
communication system became more popular system than the other system. The paper
firstly analyzed the components of maritime laser communication system, the paper
made some explanations on the components and functions of the servo system,
[attachment=66668]
ABSTRACT
Laser communication is one of the key area in wireless Communications.
This paper includes analysis, optimization, design and system level development of
signal transformation between satellites or any two sources. Which work similarly to
fiber optic links, except the beam is transmitted through free space. While the
transmitter and receiver must require line-of-sight conditions, they have the benefit of
eliminating the need for broadcast rights and buried cables. Laser communications
systems can be easily deployed since they are inexpensive, small, low power and do not
require any radio interference studies. The carrier used for the transmission signal is
typically generated by a laser diode. Two parallel beams are needed, one for
transmission and one for reception.
INTRUDUCTION
Laser Communication is one of the emerging area of wireless communication
system. Due to its low noise ratio makes its one of the well suited communication
medium for exchange of information. Currently laser commutation is adopted in satellite
communication for space research activities and due to its efficiency on low noise ratio,
inexpensive , low power and its flexibility and its resistance to the radio interferences
makes laser communication as one of research area in wireless communication. In this
process, this paper comprises the one such application of laser communication for
information exchange between any two devices.
In Laser Communication the transmitter and receiver must require a line-of-sight
conditions and Laser communications systems have the benefit of eliminating the need
for broadcast rights and buried cables. The carrier used for the transmission signal is
typically generated by a laser diode. Two parallel beams are needed, one for
transmission and one for reception.
Laser communications systems are wireless connection through the atmosphere.
Which is focused on decreasing the noise ratio in optical communication system. Laser
communications systems work similarly to fiber optic links, except the beam is
transmitted through free space. In Laser Communication the transmitter and receiver
must require a line-of-sight conditions and Laser communications systems have the
benefit of eliminating the need for broadcast rights and buried cables.
IMPLEMENTATION
The voltage variation on the solar panel is amplified by a low-voltage audio
power amplifier LM386 and reproduced by a speaker. The maximum output of
audio amplifier LM386 is 1 watt, while its voltage gain is 20 to 200. The circuit consists
of a transmitter and a receiver. Both the transmitter and the receiver are built around IC
LM386, powered by a 9V battery.
Fig. 1 shows the transmitter circuit Here a laser diode (LD1) with maximum
operating voltage of around 2.6V DC and maximum operating current of 45 mA is
used to transmit the audio signal. The voltage divider network formed by R2, R3 and
VR3 keeps the voltage as well as the current for the laser diode in the safe region. In
place of the laser diode, you can also use a laser pointer. Remove the battery from the
laser pointer. Extend two wires from terminals of LD1 and connect them to the battery
terminals of laser pointer. The spring inside the laser pointer is the negative terminal.
The output power of the laser pointer is 5 mW. Take care while working with laser, as
direct exposure to the laser beam can be hazardous to your eyes. Point the laser beam to
the solar panel. Potmeter VR1 (10-kilo-ohm) is used to change the level of the input
audio signal. The audio input (Vin) is taken from the preamplifier output of the music
system (CD player, DVD player, etc). Capacitor C2 and preset VR2 are used to vary the
gain of the LM386.
Fig. 2 shows the receiver circuit. The audio signal transmitted by the laser
diode (LD1) is received by the calculator’s solar panel and amplified by IC2. The gain
of the amplifier is fixed by capacitor C7. Preset VR4 is used to change the signal level
WORKING
Microphone Amplifier: The first step in transmitting sound is to digitize sound
waves. For this we used an electric microphone. The microphone he sold us had three
leads, which after considerable angst we decided were for power, ground, and signal.
The signal coming off the mic was far too low to be read (with any degree of precision)by the analog to digital converter. For that we are using the LM386 op-amp to increase
the power and signal. Before the signal is put through the amplifier, first put the signal
through a capacitor to remove DC, and then through a voltage divider to appropriately
bias the signal. The gain is adjusted by the resistors and for the microphone the gain is
around 50-100 (depending on how much popping and how much quality you want).
UART ( universal asynchronous receiver/transmitter) : It is a piece
of computer hardware that translates data between p
ADVANTAGES
The advantages of laser communication is that it allows very fast communication
service between two or more devices than other modes of communications.
ìì) It can provide speed more than 1GBps.So it overtakes the LAN or wireless LAN
comprehensively.
Ììì) Laser communications systems have the benefit of eliminating the need for broadcast
rights and buried cables.
Ìν) Laser communications systems can be easily deployed since they are inexpensive,
small, low power and do not require any radio interference studies. The carrier used for
the transmission signal is typically generated by a laser diode. Two parallel beams are
needed, one for transmission and one for reception.
ν) The transmitting and receiving station are smaller and lighter for given range. Less
overall power is required for the given distance and data rate. Higher data rate may be
achieved for given distance and power output.
νì) A tiny light detector may allow for superfast broadband communication over
interplanetary distances. This technology advance offers the space laser communication
system designer the flexibility to design very lightweight, high bandwidth, low-cost
communication payloads for satellites whose launch costs are a very strong function of
launch weigh.
νìì) Signals can be reproduced without distortion, even long distances. So the system
could be use for communication and cable television transmission.
ί ) A one way laser communications system that is capable of the transmission of both ẋ
text and sound.
νί)even by a minute fraction of a degree, the laser will miss by thousands of miles.
Instead of better and faster pictures, there could be no pictures.
The noise in photodiodes The main sources of noise are dark current noise, shot noise
and thermal noise in a photodiode. There is one more source of noise due to random
nature of the avalanche in an APD. The dark current noise arises due to dark current
which flows in the circuit when th
Conclusion
This is new wireless technology to transmit the data or sound signal from one section
to other section through the laser beam of the system. This system is safety and without
radiation. so it is not harm to living beings. The system can likely transmit data and
sound much faster than the other system(like 1GB/s). because of this laser
communication system became more popular system than the other system. The paper
firstly analyzed the components of maritime laser communication system, the paper
made some explanations on the components and functions of the servo system,