Analysis of soliton transmission in optical fibers with the soliton self-frequency shift being compensated by distributed frequency dependent gain

Distributed optical fiber amplifiers with frequency dependent gain can be used to compensate the soliton self-frequency shift (SSFS), which is the major problem on subpicosecond soliton pulse transmission in fibers. The characteristics of soliton evolution with SSFS being compensated by linearly frequency dependent gain are analyzed. An expression for estimating the effective distance of the compensation method, which is limited by the amplified dispersive waves at higher frequencies, is also obtained. As an example, it is shown that dispersion-shifted distributed Er/sup 3+/-doped fibers can provide almost distortion-free SSFS compensation for pulses of about 800 fs over several tens of kilometers.<>