Modern fiber-optic communication systems generally include optical transmitters that convert electrical signals into optical signals, optical fiber cables to carry the signal, optical amplifiers, and optical receivers to convert the signal back into an electrical signal. The light is a form of carrier wave that is modulated to carry information. Fiber is preferred. The diagram above shows how electronic input signals get transformed into light pulses, travel through a fiber optic cable, and are converted back into electrical signals when they reach the receiver. Unlike copper wires, which send electrical signals and suffer from resistance and interference, fibre optics offer orders of magnitude more bandwidth and. A fiber optic transceiver (also called an optical transceiver) is a compact module that both transmits and receives data signals through optical fibers.
[PDF Version]