THEORETICAL AND EXPERIMENTAL-STUDY OF SELF-FILTERING EFFECT IN CONCATENATED ERBIUM-DOPED FIBER AMPLIFIERS

This paper describes the self-filtering effect which appears in concat enated erbium-doped fiber amplifer (EDFA) systems. Employing a theoret ical model we observed how the self-filtering wavelength is affected b y the variation of some EDFA parameters, such as gain, fiber compositi on, pump wavelength and temperature. By a recirculating loop experimen t which simulates a concatenated repeater transmission system, we meas ured the evolution of the amplified spontaneous emision (ASE) spectra with the number of circulations, and with the loss of the loop. We fou nd a good agreement between the theoretical simulations and the experi ments.