Degradation of Optical Fiber Parameters During the Period of Usage: 2003 - 2019

Changing the optical fiber parameters during long-term use can not be mathematically calculated. This paper analyses the change of optical fibers from the aspect of ageing under the influence of transmitted signals and the aspect of water influences. The analysis was carried out in such a way as to compare the measurements carried out after the installation of optical cables and measurements after 16 years of use. The analysis has been shown to vary greatly the loss of fiber optic splice for different wavelengths. These different loss for wavelengths 1310 nm and 1550 nm suggest that the loss of optical fiber has increased due to the impact of water.