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Amplifier Noise & CPA Calculator

Calculate cascaded noise figure for multi-stage amplifiers and B-integral stretch requirements for CPA systems.

Optical and RF amplifier chains accumulate noise according to the Friis cascading formula: each stage's noise figure (NF) contributes in proportion to the inverse of all preceding gain. This tool's Noise Figure Cascade mode accepts up to five amplifier stages — each defined by gain (dB) and NF (dB) — and returns the system-level NF and total gain. The B-Integral / CPA mode computes the nonlinear phase accumulation (B-integral) in a chirped-pulse amplification system: given pulse energy, beam area, pulse duration, nonlinear index n₂, propagation length, and wavelength, it calculates peak intensity, total B-integral, and the minimum required temporal stretch to keep B below π — the conventional threshold for avoiding significant nonlinear distortion.

Parameters
Stage 1
dB
dB
Stage 2
dB
dB
Cascaded Noise Figure
Total noise figure
Linear: 2.552×
4.069dB
Total gain
Linear: 3162.3×
35.00dB
Number of stages
2
Abridged Optics — Amplifier Noise & CPA Calculator v1.0Noise cascade uses Friis formula. B-integral assumes flat-top temporal and spatial profiles.

All information, equations, and calculations have been compiled and verified to the best of our ability. For mission-critical applications, we recommend independent verification of all values. If you find an error, please let us know.