3.3 Design and Characteristics of SMFs
129
Fig. 3.16 Example of a dispersion performance curve for a set of single-mode fibers, where the
two slightly curved lines are found by solving Eq. (3.52)
Rec. G.652 has specified this as a maximum dispersion of 3.5 ps/(nm km) in the
1285–1330 nm region, as denoted by the bounding dashed lines in Fig. 3.16.
Example 3.15 A manufacturer’s data sheet states that a non-dispersion-shifted fiber
has a zero-dispersion wavelength of 1310 nm and a dispersion slope of 0.092 ps/(nm
2
· km). Compare the dispersions for this fiber at wavelengths of 1280 nm and 1550 nm.
Solution Using Eq. (3.52) the dispersion is
D(1280) =
λS 0
4
1 −
λ 0
λ
4
=
(1280)(0.092)
4
1 −
1310
1280
4
= −2.86 ps/(nm - km)
129
Fig. 3.16 Example of a dispersion performance curve for a set of single-mode fibers, where the
two slightly curved lines are found by solving Eq. (3.52)
Rec. G.652 has specified this as a maximum dispersion of 3.5 ps/(nm km) in the
1285–1330 nm region, as denoted by the bounding dashed lines in Fig. 3.16.
Example 3.15 A manufacturer’s data sheet states that a non-dispersion-shifted fiber
has a zero-dispersion wavelength of 1310 nm and a dispersion slope of 0.092 ps/(nm
2
· km). Compare the dispersions for this fiber at wavelengths of 1280 nm and 1550 nm.
Solution Using Eq. (3.52) the dispersion is
D(1280) =
λS 0
4
1 −
λ 0
λ
4
=
(1280)(0.092)
4
1 −
1310
1280
4
= −2.86 ps/(nm - km)