Comparison with electrical transmission(2)

In short distance and relatively low bandwidth applications, electrical transmission is often preferred because of itsLower material cost, where large quantities are not requiredLower cost of transmitters and receiversCapability to carry electrical power as well as signals (in specially-designed cables)Ease of operating transducers in linear mode.

Optical fibers are more difficult and expensive to splice than electrical conductors. And at higher powers, optical fibers are susceptible to fiber fuse, resulting in catastrophic destruction of the fiber core and damage to transmission components.

Because of these benefits of electrical transmission, optical communication is not common in short box-to-box, backplane, or chip-to-chip applications; however, optical systems on those scales have been demonstrated in the laboratory.In certain situations fiber may be used even for short distance or low bandwidth applications, due to other important features:

Immunity to electromagnetic interference, including nuclear electromagnetic pulses (although fiber can be damaged by alpha and beta radiation).

High electrical resistance, making it safe to use near high-voltage equipment or between areas with different earth potentials.Lighter weight—important, for example, in aircraft.No sparks—important in flammable or explosive gas environments.Not electromagnetically radiating, and difficult to tap without disrupting the signal—important in high-security environments.Much smaller cable size—important where pathway is limited, such as networking an existing building, where smaller channels can be drilled and space can be saved in existing cable ducts and trays.

Optical fiber cables can be installed in buildings with the same equipment that is used to install copper and coaxial cables, with some modifications due to the small size and limited pull tension and bend radius of optical cables. Optical cables can typically be installed in duct systems in spans of 6000 meters or more depending on the duct's condition, layout of the duct system, and installation technique. Longer cables can be coiled at an intermediate point and pulled farther into the duct system as necessary.

June 7, 2011

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