26-03-2012, 12:22 PM
AN OPTICAL COMMUNICATION SYSTEM WITHOUT FIBERS
FREE_SPACE_OPTICS.pdf (Size: 57.94 KB / Downloads: 90)
INTRODUCTION
Communication, as it has always been relied and simply depended
upon speed. The faster the means ! the more popular, the more effective the
communication is !
Presently in the twenty-first centaury wireless networking is gaining
because of speed and ease of deployment and relatively high network
robustness. Modern era of optical communication originated with the
invention of LASER in 1958 and fabrication of low-loss optical fiber in
1970.
When we hear of optical communications we all think of optical
fibers, what I have for u today is AN OPTICAL COMMUNICATION
SYSTEM WITHOUT FIBERS or in other words WIRE FREE OPTICS.
FSO ! FREE SPACE OPTICS
Free space optics or FSO, free space photonics or optical wireless,
refers to the transmission of modulated visible or infrared beams through
the atmosphere to obtain optical communication. FSO systems can function
over distances of several kilometers.
FSO is a line-of-sight technology, which enables optical
transmission up to 2.5 Gbps of data, voice and video communications,
allowing optical connectivity without deploying fiber optic cable or
securing spectrum licenses. Free space optics require light, which can be
focused by using either light emitting diodes (LED) or LASERS(light
amplification by stimulated emission of radiation). The use of lasers is a
simple concept similar to optical transmissions using fiber-optic cables, the
only difference being the medium.
RELEVANCE OF FSO IN PRESENT DAY COMMUNICATION
Presently we are faced with a burgeoning demand for high
bandwidth and differentiated data services. Network traffic doubles every
9-12 months forcing the bandwidth or data storing capacity to grow and
keep pare with this increase. The right solution for the pressing demand is
the untapped bandwidth potential of optical communications.
Optical communications are in the process of evolving Giga bits/sec
to terabits/sec and eventually to pentabits/sec. The explosion of internet
and internet based applications has fuelled the bandwidth requirements.
Business applications have grown out of the physical boundaries of the
enterprise and gone wide area linking remote vendors, suppliers, and
customers in a new web of business applications. Hence companies are
looking for high bandwidth last mile options. The high initial cost and vast
time required for installation in case of OFC speaks for a wireless
technology for high bandwidth last mile connectivity there FSO finds its
place.