Erbium-Doped Fiber Amplifier, a length of erbium-doped fiber pumped at 980 or 1480 nm that amplifies all channels in the C-band, about 1530 to 1565 nm, at once, with gains of 20 to 30 dB. Its noise figure, typically 4.5 to 6 dB against a 3 dB quantum limit, sets how many amplifiers can be cascaded. In labs EDFAs are the default way to boost a 1.5 µm seed for experiments.
Put the EDFA after the modulator to win back its insertion loss before the signal goes out on the long fiber run.
Also heard as
- erbium amplifier
- erbium-doped fiber amplifier
Related terms
ASE
Amplified Spontaneous Emission: random spontaneous photons amplified in a gain medium, a broadband noise background.
Gain saturation
The drop in an amplifier's gain as the signal grows strong enough to deplete the stored inversion.
MOPA
Master Oscillator Power Amplifier: a low-power seed laser followed by amplifier stages that bring it to full power.
Fiber laser
A laser whose gain medium is an optical fiber with a rare-earth-doped core, pumped by diodes.