Fig. 1. Schematic diagram of the BOTDA system

Fig. 2. Structure diagram of multilayer perceptron^[12]

Fig. 3. Temperature curve of optical fiber in submarine cable as a function of distance

Fig. 4. Temperature curve of a single sampling point in a submarine cable with time

Fig. 5. Algorithm flowchart

Fig. 6. Accuracy curve with the number of training rounds

Fig. 7. PR curves

Fig. 8. The relationship between the distance of the optical fiber in the submarine cable and the buried depth