2025-08-06
A Physics-Assisted Learning Method Based on the Improved U-Net for Reconstructing 2-d Dielectric Objects
By
Progress In Electromagnetics Research B, Vol. 114, 89-98, 2025
Abstract
In the past few years, deep learning has emerged as a transformative force in tackling challenges within the realm of electromagnetic inverse scattering, driving remarkable advances and reshaping conventional approaches. Among them, the physics-assisted learning method that combines traditional inverse scattering algorithms with deep neural networks has demonstrated excellent real-time inversion capability and lower computational complexity. For two-dimensional inverse scattering problems, an approximate solution of the target is first obtained using a linear approximation algorithm, followed by mapping learning from low to high precision with a neural network. To enhance both precision and generalizability, this study integrates a Transformer module into a CBAM U-Net framework, giving rise to a refined architecture aptly named TransAtten U-Net. By retaining certain positional information while enhancing the correlations between features, the overall feature extraction effect is improved. Through simulation experiments, the paper compares the performance of the proposed TransAtten U-Net two-step method, TransAtten U-Net direct method, and CBAM U-Net two-step method. Experimental results demonstrate that the proposed TransAtten U-Net two-step method not only achieves higher accuracy than the other two approaches, but also exhibits a stronger generalization capability across diverse scenarios, along with enabling real-time imaging.
Citation
Zhangyue Zhao, and Chunxia Yang, "A Physics-Assisted Learning Method Based on the Improved U-Net for Reconstructing 2-d Dielectric Objects," Progress In Electromagnetics Research B, Vol. 114, 89-98, 2025.
doi:10.2528/PIERB25041707
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