EDFA applications can be divided into the function used for long distance transmission line amplifier, is used as the light transmitter output power amplifier and used as a preamplifier receiver front-end.
(1) the power amplifier
After the EDFA in the optical transmitter semiconductor laser, optical signal by EDFA enlarged into fiber optic lines, thus make optical fiber transmission WuZhongJi distance increases, can reach more than 200 km.Has a large output power, output stability, low noise, wide frequency band, easy to monitor, etc.
(2) the line amplifier
In a power amplifier, is used to periodically compensation circuit transmission loss, generally require smaller noise index, larger output optical power.EDFA as line amplifier has many special features is incomparable in electronic circuit amplifier.
(3) the preamplifier
In the partial wave before and after line amplifier, is used for signal amplification, improve the receiver sensitivity.EDFA is close to the quantum limit of the advantages of low noise, and therefore the preamplifier can be used as a receiver in order to improve the receiving sensitivity, noise figure is small, the output power is not too big.The EDFA in the optical receiver PIN in the front of the light side of the detector, the signals from the optical fiber by EDFA enlarged again by PIN detection.Strong light signals to make electronic amplifier noise can be ignored, made preliminary put EDFA optical receiver has higher sensitivity.
If integrated these various applications, an optical fiber amplifier is used as the receiver preamplifier, another EDFA as a transmitter power amplifier, can realize the long-distance WuZhongJi transmission.This type of system is mainly used for undersea optical fiber communication system.
In this paper, published by shandong Wan Shuo photoelectric equipment co., LTD.