Patent ID: 6876803

Claim:
An optical transmission system having an optical transmission path comprising: a plurality, n, of connected sets of transmission path spans each formed of an optical fiber for transmission having positive wavelength dispersion and positive dispersion slope, and a dispersion compensating fiber having negative wavelength dispersion and negative dispersion slope, in an operating wavelength band; wherein, the dispersion slope and optical fiber length of the optical fiber for transmission and the dispersion compensating fiber satisfy equations (1), (2) and (3) for each transmission path span: a ≤ ( St i ⁢ Lt i ) + ( Sd i ⁢ Ld i ) ( Lt i + Ld i ) ≤ b ( 1 ) b≠0 (3) and satisfy equations (4) and (5) for the overall optical transmission path: c ≤ ∑ i = 1 n ⁢ St i ⁢ Lt i + ∑ i = 1 n ⁢ Sd i ⁢ Ld i ∑ i = 1 n ⁢ ( Lt i + Ld i ) ≤ d ( 4 ) wherein in equations (1), (2), (3), (4) and (5), St i and Lt i respectively represent the dispersion slope and optical fiber length of the optical fiber for transmission in each transmission path span, Sd i and Ld i respectively represent the dispersion slope and optical fiber length of the dispersion compensating fiber in each transmission path span, and a, b, c and d are constants that define the residual dispersion slope.