Tuesday, 22 November 2016

Fiber optic cables

  • A fiber optic cable consists of a bundle of glass threads, each of which is capable of transmitting data onto light waves.
  • It is a high speed data transmission medium, can send data in the speed of light.
  • The receiving end of a fiber optic transmission translates the light pulses into binary values, which can be read by a computer.
  • It uses in commercial business, governments, the military, now it also used by internet service provider.


Types

Multi-mode fiber
  • In a multi-mode fiber, the core diameter is much bigger than the wavelength of the transmitted light.
  • It can carry multiple light rays or modes concurrently, each at a slightly different reflection angle within the optical fiber core.
  • Multi-mode fiber transmission is used for relatively short distances because the modes tend to disperse over longer lengths.
  • Because of its high capacity and reliability, multi-mode optical fiber generally is used for backbone applications in buildings.


Single-mode fiber
  • A type of fiber with a small core that allows only one mode of light to transmit.
  • There more information can be transmitted per unit of time.
  • Single-mode fiber allows for a higher capacity to transmit information.
  • Single-mode cable used by telephone industries for long distance telecommunication.


Advantages

  • Extremely high bandwidth
  • It can also be run in electrically noisy environments without concern as electrical noise will not affect fiber.
  • An optical fiber offers low power loss.
  • Fiber optic cables are much thinner and lighter than metal wires.
  • Fiber do not lose any light, therefore the transmission is also secure and cannot be disturbed.
  • Lightness and small size of the cable, capable of carrying a large number of signals.
  • As optical fiber has no electrical conductivity, therefore grounding and protection are not necessary.
  • Easily can install.

Disadvantages

  • The glass can be affected by various chemicals including hydrogen gas.
  • Transmission on optical fiber requires repeating at distance intervals.
  • Fibers can be broken or have transmission losses when wrapped around curves of only a few centimeters radius.
  • Special test equipment is required.
  • Optical fibers are more costly.

Applications




My notes



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