SAR-ATR with knowledge hierarchy division and information dissemination networks

Synthetic aperture radar (SAR) images possess diverse domain characteristics that describe targets from multiple perspectives, including scattering center, intensity, phase, azimuth angle, and shadow. The imaging mechanism of SAR images significantly differs from optical images due to its use of radio waves instead of visible light for imaging purposes. However, current deep learning (DL)-based automatic target recognition (ATR) approaches for SAR primarily focus on the intensity information while neglecting the comprehensive consideration of SAR domain characteristics. This limitation results in insufficient expression of target features and hampers further improvement in SAR target recognition performance. To address these issues, this paper proposes a novel SAR target recognition method called KDNets based on information dissemination networks (IDNets) and knowledge hierarchy division (KnHD). KDNets effectively enhances the feature representation ability of SAR targets by exploiting multiple domain characteristics at sample, feature, and decision levels. Specifically, IDNets incorporates scattering center and azimuth angle at sample and feature levels to extract rich multi-scale semantic features for representing SAR targets. At the decision stage, KnHD utilizes azimuth information to rapidly search and fuse prior knowledge about targets from a knowledge base to achieve interpretable and high-precision SAR target recognition. Experimental results on the MSTAR dataset and MA-SAR dataset demonstrate that our proposed KDNets can achieve state-of-the-art performance in SAR target recognition tasks, with the accuracy of 99.75 % in the MSTAR dataset and 98.61 % in the MA-SAR dataset, validating its effectiveness and superiority. Furthermore, this study highlights the significant potential and application prospects of leveraging domain characteristics in SAR-ATR tasks.