Basically precisely what the FTTH drop cable production line solve is the traditional distance problem like any great distance telecommunication system such as a trans-Atlantic link. As optical signals travel through the fiber, the signals become weaker in power. The farther you are going, the weaker the signal become until it might be too weak to become detected reliably.
Fiber optic communication systems solve this issue by using fiber amplifiers along the way. A repeater or amplifier is inserted in to the system with a point the location where the signal has grown to be weak, to improve the effectiveness of the signal so it could be transmitted through another duration of fiber cable. Many amplifiers or repeaters may be placed in sequence to maintain the signal strong across the whole fiber link.
Traditionally, electronic repeaters were utilized for optical signal amplification. A repeater is an opto-electro-opto device. It converts a weak optical signal into electronic signal, cleans up the electronic signal, and after that converts the electronic signal back to optical signal having a lightwave transmitter. The lightwave transmitter emits much stronger power compared to incoming optical signal and therefore amplifies it.
However, this is an inconvenient and expensive process and which explains why it really 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 at all. Basically, you may consider it a in-line laser. And SZ stranding line can simultaneously amplify dozens of optical channels simply because they will not convert each channel into electronic signals separately.
The atoms of erbium or praseodymium may be pumped by high power light (pump laser) into excited state. But are not stable within the excited state. Once the optical signals that are to be amplified pass though the 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 such as emitted light photons as well. The emitted photons have similar phase and wavelength because the input optical signal, thus amplify the optical signal.
This really is a very convenient form of amplifier on an optical fiber communication system since it is an in-line amplifier, thus removes the requirement to perform optical-electrical and electrical-optical conversion process.
The pump laser wavelengths and also the corresponding optical signal wavelengths are key parameters for operation of fiber amplifiers. These wavelengths be determined by the particular 12dextpky element doped from the Optical fiber coloring machine and also to the composition from the glass within the fiber.
Another essential term in understanding fiber amplifiers is its “gain”. Gain measures the amplification per unit duration of fiber. Gain depends on both the materials and also the operating conditions, and yes 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 top input powers, the gain saturation effect is needed. So increment of input power produces less output power, which essentially means the amplifier has exhaust your the strength it requires to generate more output.