In this work we present realization of amplified optical communication system at different data transmission speeds and distances. To suppress amplified spontaneous emission of erbium doped fiber amplifier we use tunable bandwidth flat-top band pass optical filter. Investigation of this problem is important because of great role of optical amplifiers in optical communication systems. The used simulation program realizes method of calculation that is based on solving a complex set of differential equations, taking into account optical and elec-trical noise, linear and nonlinear effects [1].