Attenuation Characteristics: G. 652 fiber has the lowest attenuation at wavelengths of 1310 nm and 1550 nm, approximately 0. 652 fiber highly suitable for long-distance transmission. It details the fiber's geometrical, optical. G652: Defined in ITU-T Recommendation G. Its low attenuation (signal loss) and compatibility with existing infrastructure made it the global standard for decades. Testing in both directions and averaging gives the actual. G. Each fiber type is engineered with different refractive index profiles, dispersion properties, and bending performance to support specific applications—from long-distance. G652 fibers are single-mode optical fibers with zero dispersion around the wavelength of 1310 nm, but you can also use them in the 1550 nm region.