Detailed Description of Correlation Method for Longitudinal Power Profile Estimation

Power profile estimation is one of the key instruments for creating digital twins of real networks. One way to get a power profile is to upgrade digital signal processing algorithms. However, the description of additional blocks to traditional digital signal processing algorithms presented in published articles is incomplete. The paper presents a step-bystep algorithm for restoring the signal power profile along a fiber-optic communication line using the correlation method as an additional instrument to digital signal processing at the receiver. The effectiveness of the algorithms was demonstrated by processing signals obtained in numerical simulations and experimental data. Numerical simulations were carried out using the VPIphotonics software package. Experimental data was obtained from the operation of high-speed communication systems consisting of 6 spans of standard single-mode fiber 100 km long each. Limitations on the minimum power obtained using this method are given. The possibility of searching for an anomaly element using the described method was demonstrated.