Analysis of stabilizing effect of filters in dispersion-managed soliton systems

Recent studies of dispersion-managed solitons show that their pulse energy in the steady state is larger than that of the conventional soliton with the same (minimum) pulse width and the same (averaged) fiber dispersion [1]. The enhanced pulse energy reduces the relative effect of noise emitted from inline optical amplifiers, which can extend the transmission distance. This indicates that the use of control schemes such as frequency-sliding filters and synchronous modulation may not be needed in the dispersion-managed soliton systems [2]. The use of filters with appropriate bandwidth, however, can be beneficial to increase further the system length [3]. The filters may also be effective to reduce mutual interaction between adjacent pulses that is one of the factors limiting the performance of dispersion-managed solitons with strong power enhancement. The author previously carried out a semi-numerical analysis of the effect of filters on the dispersion-managed soliton (stretched pulse) transmission [4]. In this paper analytical expressions for the strength of stabilizing pulse energy and frequency by the filters are given.