Basically exactly what the Fibers in stainless steel tube. solve may be the traditional distance problem like any long distance telecommunication system for instance a trans-Atlantic link. As optical signals travel with the fiber, the signals become weaker in power. The farther you choose to go, the weaker the signal become until it will become too weak to be detected reliably.
Fiber optic communication systems solve this issue by making use of fiber amplifiers along the way. A repeater or amplifier is inserted into the system with a point where signal is becoming weak, to improve the effectiveness of the signal so it might be transmitted through another duration of fiber cable. Many amplifiers or repeaters can be put in sequence to help keep the signal strong down the whole fiber link.
Traditionally, electronic repeaters were utilised for optical signal amplification. A repeater is an opto-electro-opto device. It converts a weak optical signal into electronic signal, cleans in the electronic signal, and then converts the electronic signal returning to optical signal with a lightwave transmitter. The lightwave transmitter emits much stronger power compared to the incoming optical signal and therefore amplifies it.
However, it is really an inconvenient and expensive process and which is the reason this has been replaced from the new optical fiber amplifiers technology.
An optical fiber amplifier is a purely optical device. It doesn’t convert the incoming optical signal to electronic signal whatsoever. Basically, it is possible to consider it a in-line laser. And optical fiber ribbon machine can simultaneously amplify many optical channels because they tend not to convert each channel into electronic signals separately.
The atoms of erbium or praseodymium could be pumped by high power light (pump laser) into excited state. However they are not stable from the excited state. When the optical signals that have to be amplified pass even though fiber, they stimulate the excited erbium atoms. The erbium atoms will jump through the high power level excited state into low power level stable state, and release their energy in the form of emitted light photons at the same time. The emitted photons have a similar phase and wavelength as being the input optical signal, thus amplify the optical signal.
This can be a very convenient method of amplifier on an optical fiber communication system because it is an in-line amplifier, thus removes the need to perform the optical-electrical and electrical-optical conversion process.
The pump laser wavelengths and the corresponding optical signal wavelengths are key parameters for operation of fiber amplifiers. These wavelengths depend upon the sort of 12dextpky element doped within the Sheathing line and also on the composition in the glass from the fiber.
Another important term in understanding fiber amplifiers is its “gain”. Gain measures the amplification per unit time period of fiber. Gain depends upon the materials along with the operating conditions, and it varies with wavelength for all materials.
For low input powers, the output power is proportional towards the gains times the fiber length. Thus, P(output) = P(input) x Gain x Length
For high input powers, the gain saturation effect comes into play. So increment of input power produces less output power, which essentially means the amplifier has exhaust your the strength it needs to generate more output.