23-11-2012, 02:12 PM
THE NEXT GENERATION WIRELESS TECHONOLOGY FREE SPACE OPTICS(FSO)
THE NEXT GENERATION.pptx (Size: 97.84 KB / Downloads: 24)
INTRODUCTION
Most latest technology-No cable required-can withstand radio jamming
Point to point-line of sight broadband solution.
Provide high speed optical band width to the ultimate end user.
Zero sunk-cost solution.
Low cost then fiber-less lined-employed in less number of days
Band width can be easily be scaled( 10 mbps to 1.25 gbps)
Use same optical transmission wavelength as fiber and had same component as fiber.
Uses wavelength division multiplex techonology and EDFA.
Working:
It consists of FSO based optical wireless units, each consisting of
optical transceiver which operated in full duplex mode, plus a lens or telescope that transmits light through the atmosphere to another lens receiving the information,the receiving lens or telescope connects to a
high-sensitivity receiver via optical fiber.
Uses discrete diode for coupling the laser to output aperture.
For low power laser driver chips is used and for high power laser RF amplifiers is used.
Detectors are generally either PIN diodes or avalanche photodiodes(APD). Usually trans-impedance amplifier used after detectors to provide high gain with fastest speed
Security:
FSO systems operating in the near infrared wavelength range do not require licenses worldwide for operation.
FSO systems operate in the near infrared wavelength range slightly above the visible spectrum. Therefore, the human eye cannot visibly see the transmission beam.
The wavelength range around 1 micrometer that is used in FSO transmission systems is actually the same wavelength range used in fiber-optic transmission systems. The wavelength range around 1 micrometer translates into frequencies of several hundred terahertz (THz)
which is higher than that used in commercially available microwave communications systems operating around 40 GHz.FSO systems use very narrow beams that are typically much less than 0.5 degrees.
Uses WEP-to protect the transmission path from being intercepted.
CONCLUSION
FSO allows them to provide this optical connectivity cost effectively, quickly and reliably.
Such flexibility makes FSO systems an extremely attractive method for service providers to truly solve the connectivity bottleneck.
Free-Space Optics communication systems are among the most secure networking transmission technologies.
FSO may be used in conjunction with other technologies to expand their current networks , such as Terabeam, see the technology as a means to break into the broadband market."