Can anyone explain the bandwidth of Optical Fiber.?
The bandwidth of an optical fiber is a function of the distance you want the optical signal to travel. There are three major factors that limit long distance transmission. The first is attenuation, the second is dispersion and the third is pulse spreading. Pulse spreading is controlled by using a single mode fiber. Attenuation is improved with very pure glass. The best attenuation performance is found to occur at 1550 nm. The effects of dispersion are a minimum at 1310 nm. There has been much work on shifting the dispersion minimum to match the attenuation minimum at 1500 nm. Employing the narrow “window” at just one of these minimums, to achieve maximum unamplified transmission length, and using DWDM (Dense Wavelength Division Multiplexing), which allows for 160 independent modulation channels, where each laser is capable of 40GHz modulation rate, yields total data transmission rate of 6.4 Terabits per second. For shorter transmission lengths the bandwidth could be much wider.
