EDFA Gain Calculator

Calculate erbium-doped fiber amplifier performance for optical networks.

Input Signal

EDFA Parameters

Typical: 4-6 dB
Total output limit

System Requirements

Depends on modulation format

OSNR Requirements by Modulation

Modulation Data Rate Min OSNR
OOK NRZ10G14 dB
DP-QPSK100G12 dB
DP-8QAM200G17 dB
DP-16QAM200G/400G20 dB
DP-64QAM400G/600G26 dB

Values at BER = 1e-3 with FEC

EDFA Theory

OSNR Calculation

OSNR = Pin + G - NF - 10*log10(h*v*Bref) - 30
Where h*v = 1.28e-19 J at 1550nm, Bref = reference bandwidth

EDFA amplifies both signal and noise. The ASE (Amplified Spontaneous Emission) noise accumulates with each amplifier in a chain, degrading OSNR.

EDFA Types

  • Booster: After transmitter, high output power
  • In-Line: Compensate fiber loss, balanced design
  • Pre-Amp: Before receiver, low noise figure critical
  • Gain Flatness: Critical for DWDM systems
  • Typical NF: 4-6 dB for quality EDFAs