Power evolution prediction of bidirectional Raman amplified WDM system based on a transformer

This study presents a transformer-based power prediction model for Raman-amplified wavelength division multiplexing (WDM) systems. Leveraging the transformer's self-attention mechanism, the model effectively captures global channel interactions, achieving a maximum prediction error of only 0.122 dB in a 200 km bidirectional Raman system with 47 channels and 12 pumps. The differential evolution (DE) technique was employed to optimize the hyperparameters of the models, further enhancing their performance. The comparative analysis was conducted to evaluate the performance of the two models under their respective optimal configurations. The model demonstrates robust generalization under varying pump powers and surpasses convolutional neural network (CNN)-based approaches in accuracy and interpretability.