A Novel Pseudo-Siamese Fusion Network for Enhancing Semantic Segmentation of Building Areas in Synthetic Aperture Radar Images

Segmenting building areas from synthetic aperture radar (SAR) images holds significant research value and practical application potential. However, the complexity of the environment, the diversity of building shapes, and the interference from speckle noise have made building area segmentation from SAR images a challenging research topic. Compared to traditional methods, deep learning-driven approaches exhibit superiority in the aspect of stability and efficiency. Currently, most segmentation methods use a single neural network to encode SAR images, then decode them through interpolation or transpose convolution operations, and finally obtain the segmented building area images using a loss function. Although effective, the methods result in the loss of detailed information and do not fully extract the deep-level features of building areas. Therefore, we propose an innovative network named PSANet. First, two sets of deep-level features of building areas were extracted using ResNet-18 and ResNet-34, with five encoded features of varying scales obtained through a fusion algorithm. Meanwhile, information on the deepest-level encoded features was enriched utilizing an atrous spatial pyramid pooling module. Next, the encoded features were reconstructed through skip connections and transposed convolution operations to obtain discriminative features of the building areas. Finally, the model was optimized using the combined CE-Dice loss function to achieve superior performance. The experimental results of the SAR images from regions with different geographical characteristics demonstrate that the proposed PSANet outperforms several recent State-of-the-Art methods.