Need for optical fiber amplifiers
Optical amplifier EDFA solves the traditional distance problem as in any long-distance telecommunication system such as a trans-Atlantic link. The signals become weaker in power because optical signals travel through the fiber. The signal become weaker if you go far until it becomes too weak to be detected reliably.
Optical fiber amplifiers and their working
An optical fiber amplifier is a part of optical fiber that is doped with a rare-earth element such as erbium or praseodymium.
By high power light (pump laser) the atoms of erbium or praseodymium can be pumped into an excited state. But in the excited state, they are not at all stable. When there is a need for optical signals to be amplified then it is required that they should pass through the fiber as they stimulate the excited erbium atoms. The erbium atoms will then jump from the high-power level excited state into a low power level stable state, and at the same time, it releases their energy in the form of emitted light photons. Like the input optical signal, the emitted photons have the same phase and wavelength thus amplifying the optical signal.
This is a very convenient form of the amplifier, especially for an optical fiber communication system as it is an in-line amplifier. It then removes the need to do the optical-electrical and electrical-optical conversion process.
Cooperation of fiber optical attenuator pumps the laser wavelengths and the corresponding optical signal wavelengths are key parameters. These wavelengths rely on the type of rare-earth element doped in the fiber and also on the composition of the glass in the fiber.
Gain is another important term in understanding fiber amplifiers. The amplification per unit length of fiber is measured in gain. The gain depends on both the materials and the operating conditions, and it differs with wavelength for all materials.
In the case of low input powers, the output power is proportional to the gains times the fiber length.
The gain saturation effect comes into play for high input powers. So, an increment of input power produces less and less output power, which means that the optical switch has run out of the power it needs to generate more output.
FiberMART INC.
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Tel : +1 (707)-702-1573
Fax: +1 (707)-424-8352
E-mail: sales@fiber-mart.com
China (Manufacturing R & D)
Mingyuan Road, Optic Valley, Hongshan Distric, Wuhan 430074, Hubei Province, P.R. China
Tel : +86-27-872-080-18 +86-1-86-2786-1199
Fax: +86-27 598-056-33
E-mail: sales@fiber-mart.com
Mingyuan Road, Optic Valley, Hongshan Distric, Wuhan 430074, Hubei Province, P.R. China
Tel : +86-27-872-080-18 +86-1-86-2786-1199
Fax: +86-27 598-056-33
E-mail: sales@fiber-mart.com
