Glimpse of Optical Fiber Standards

1. Optical fiber Standards
I am Proud to be the part of the organization that patented these Grand standards for Optical Communication.

2. Page 2
According to ITU-T, three types of single-mode optical fibers are defined in G.652, G.653, and G.655
respectively. The differences between them are shown in the following table:
Type Definition Scope Main Specifications
G.652
The standard single-mode fiber (SMF)
refers to the fiber whose zero-
dispersion point (the zero-dispersion
wavelength) is near to 1310 nm.
Used in both SDH
system and DWDM
system
Attenuation: The attenuation value of the 1310 nm band is 0.3–0.4
dB/km and the typical value is 0.35 dB/km. The attenuation value of the
1550 nm band is 0.17–0.25 dB/km and the typical value is 0.20 dB/km.
Dispersion: The allowed value of the zero-dispersion wavelength is
1300–1324 nm. The dispersion coefficient of the 1550 nm band is
positive and the typical value of the dispersion coefficient D is 17
ps/(nm.km). The maximum value is not more than 20 ps/(nm.km).
G.653
Dispersion-shifted fiber (DSF) refers
to the fiber whose zero-dispersion
point is near to 1550 nm. Compared
with G.652 SMF, the zero-dispersion
point of G.653 DSF shifts.
Used in the SDH
system but not in the
DWDM system
Attenuation: The attenuation value of the 1310 nm band is less than
0.55 dB/km and the typical value has not been confirmed. The
attenuation value of the 1550 nm band is less than 0.35 dB/km and the
typical value is 0.19–0.25 dB/km.
Dispersion: The wavelengths in the G.653 DSF are near to 1550 nm,
usually 1525–1575 nm. The maximum dispersion coefficient is 3.5
ps/(nm.km). The dispersion coefficient in the DSF is too small or may
be 0 for 1550 nm bands, especially C band.
G.655
Non-zero dispersion-shifted fiber
(NZDSF) refers to the fiber whose
zero-dispersion point is shifted away
from 1550 nm and not within the
DWDM operating wavelength range
near to 1550 nm.
Used in both SDH
system and DWDM
system, but more
applicable to the DWDM
system
Attenuation: The attenuation value of the 1310 nm band is not specified
in ITU-T. The attenuation value of the 1550 nm band is less than 0.35
dB/km, usually 0.19–0.25 dB/km.
Dispersion: If 1530 nm <  < 1565 nm, 0.1 ps/(nm.km) < |D(λ)| < 6.0
ps/(nm.km). The typical value of the dispersion coefficient of the G.655
NZDSF varies with vendors and needs to be confirmed based on actual
situations, usually 4.5 ps/(nm.km) and 6 ps/(nm.km).
G.652/G.653/G.655 Single-Mode Optical Fibers

3. Page 3
Characteristics of G.652/G.653/G.655 Fibers
Dispersion coefficient
ps/(nm·km)
Positive dispersion coefficient of
G.655 NZDSF
Wavelength  (nm)
15501310
17
1.The minimum dispersion and attenuation in the
1550 nm band, applicable to the DWDM system and
able to transmit signals at a high speed.
2.Applications: TrueWave fibers (SPM effects in the
positive dispersion area facilitate transmission) and
LEAF-large effective area fibers (non-linear effects are
weakened)
G.652 SMF: large-scale laying, high-
speed transmission and dispersion
compensation
G.653 DSF: serious frequency mixture in
the 1550 nm band and not applicable to
the DWDM system
Negative dispersion
coefficient of G.655 NZDSF
G.654
Similar to G.653 DSF but different in cut-off
wavelengths. The cut-off wavelength in G.654
fiber is 1530 nm.
Full
wavelength
fiber
Eliminating the "water peak" gain at 1380 nm.