IPILT–OHPL: An Over-the-Horizon Propagation Loss Prediction Model Established by Incorporating Prior Information Into the LSTM–Transformer Structure

Abstract

The evaporation duct is a prevalent atmospheric structure in the marine lower troposphere with significant regional nonuniformity. This structure can trap radio waves inside its layer and enable them to propagate over the horizon with less loss. Therefore, accurately predicting the over-the-horizon propagation loss (OHPL) is important for optimizing the performance of radio-electronic systems. Considering the OHPL characteristics in nonuniform evaporation ducts, this article establishes an OHPL prediction model by incorporating prior information into the long short-term memory (LSTM)–transformer structure (IPILT–OHPL). The combination of the LSTM network and transformer is used to construct the LSTM–transformer, aimed at leveraging their respective strengths to extract important features of OHPL effectively. In addition, to improve the prediction accuracy, this article incorporates the evaporation duct height as an environmental prior information into the LSTM–transformer. Finally, this article comprehensively evaluates IPILT–OHPL model performance in different application scenarios. The evaluation results show that the established model not only has high prediction accuracy but also strong generalization ability, which provides a new method for efficiently predicting the OHPL in nonuniform evaporation ducts.

Keywords

• Evaporation duct
• long short-term memory (LSTM) network
• over-the-horizon propagation loss (OHPL)
• prediction
• transformer