In recent years, a new type of optical fiber, G.654E, has been used in some long-distance backbone lines and has achieved good results. So, what is G.654E optical fiber? Will G.654E fiber replace traditional G.652D fiber?
In the mid-1980s, to meet the long-distance communication requirements of submarine fiber optic cables, a single-mode optical fiber with a pure silica core and a wavelength of 1550 nm was developed. Its attenuation near this wavelength is 10% lower than that of Fiber optics G.652 above.
This type of fiber is defined as G.654 fiber, and its name at that time was "minimum attenuation single-mode fiber with a wavelength of 1550 nm".
In the 1990s, WDM technology began to be used in underwater optical communication systems. WDM technology allows the simultaneous transmission of dozens or even hundreds of optical channels over a single optical fiber, and with the use of fiber optic amplifiers, high-power, multi-wavelength optical signals are coupled into a single fiber and combined at a small interface. These signals exhibit nonlinear characteristics.
Due to the nonlinear effect of optical fiber, when the optical power entering the fiber exceeds a certain value, the transmission performance of the system will gradually decrease with increasing optical power entering the fiber.
The nonlinear effect of optical fiber is related to the optical power density of the fiber core. When the input optical power is constant, increasing the effective cross-sectional area of the optical fiber and reducing the optical power density of the fiber core can reduce the influence of the nonlinear effect on transmission performance. Therefore, G.654 optical fiber began to generate controversy due to its increased effective cross-sectional area.
Increasing the effective area of the fiber will lead to an increase in the cutoff wavelength, but the increase in the cutoff wavelength must be controlled so as not to affect the use of the fiber in the C band (1530nm~1565nm), therefore, the cutoff wavelength of the G.654 fiber is set at 1530nm.
In 2000, when the ITU revised the G.654 optical fiber standard, it changed the name to “cut wavelength-shifted single-mode optical fiber”.
Until now, G.654 optical fiber has been characterized by low attenuation and a large effective area. Subsequently, G.654 optical fiber used for submarine cable communication was primarily optimized for attenuation and effective area, and gradually developed into four subcategories: A, B, C, and D.
Post time: Jan-10-2023
