Amplified spontaneous emission in soliton transmission systems employing sliding filters

The growth of the amplified spontaneous emission (ASE) noise in a soliton line employing sliding filters is studied. An analytical expression of the integrated ASE power is given for constant line dispersion. For large dispersion variations caused by the combined effect of sliding and third-order dispersion of the line, an optimal sliding rate exists that minimizes the amplified spontaneous emission. Methods to reduce the spontaneous emission at the line output are proposed.