A variable gain optical amplifier and a constant bandwidth, and the automatic compensation of the variations of the losses in an optical link comprising such an amplifier

摘要

Its gain is adjusted by a signal (g) of the control of gain can take m discrete values. According to one embodiment, it comprises: & br / - m amplifiers (g1,.., gm) having each a gain which is fixed and different gains of the other amplifiers, and a passband which is identical to that of the other; & br / - an optical switch (sw1) having an input (e) coupled to the input (ea) of the variable gain amplifier (avg1), m outputs (s1,.., sm) respectively coupled to the inputs of the m amplifiers (g1,.., gm) to a gain which is fixed, and a control input receiving the signal (g) of the gain control; & br / - and an optical switch (sw2) with m inputs (e1,.., em) respectively coupled to the outputs of the m amplifiers (g1,.., gm) to gain set, an output (sc) coupled to the output (its) of the variable gain amplifier (avg1), and a control input receiving the signal (g) of the gain control. & br / application to the optical connections to a great distance and spectral multiplexing.