| An analysis technique for sub-picosecond pulse propagation in an erbium-doped fiber amplifier (EDFA) was proposed that could be applied to the entire bandwidth range of the device. The model was developed directly from measured absorption and emission cross-section data, and included pump depletion and amplified spontaneous emission.; Linear and nonlinear pulse propagation were studied parametrically. An expression was derived for the pulse broadening factor (PBF). In the linear regime, the PBF equation was found to provide excellent agreement with numerical results for picosecond pulses, and for a high concentration EDFA. For shorter pulses, the PBF equation and numerical predictions deviated. This was a result of cubic and higher order dispersion effects, which were not included in the PBF equation. For a low concentration EDFA, host effects dominated and the PBF equation and numerical results agreed closely for all pulse widths and gains.; Solitonic pulse propagation was analyzed for a fundamental soliton input and for a unity gain. For the high concentration case, it was shown that the pulse did not maintain the input soliton characteristic with distance, as a result of erbium gain dispersion. For the low concentration case, the solitonic nature was preserved for all tested wavelengths and input pulse widths. The results suggest that it is desirable to propagate solitons in a long length, low concentration EDFA. |
