This thesis presents a study of single channel amplified soliton systems base don numerical simulations. In these systems, the losses of the optical fibers are compensated by the periodic insertion of Erbium-doped fiber amplifiers (EDFAs). As the amplifiers generate noise in the form of spontaneous amplified emission (ASE noise), their presence limits the systems performance. The resulting limitations - the Gordon-Haus effect, ASE noise accumulation, length of the amplifier span and interaction between neighborinhg pulses - are analyzed in detail. When taken into account, these limitations make the performance of amplied soliton systems inferior to that of classical linear NZR systems currently in use. Different techniques to improve the performance of soliton systems are investigated, mainly the dispersion management tecnique and spectral flitering, using both fixed and sliding frequencies. The results obtained through extensive numerical simulations allow a sound evaluation of the applicability of amplified soliton systems to long distance and/or high rate transmissions.