Abstract:For automatic modulation classification in intelligent spectrum monitoring under dynamic electromagnetic environments, where high model complexity and insufficient robustness at low signal-to-noise ratios remain challenging, a graph MinCut-clustering attention based method was investigated. Signal nodes were constructed by using I/Q dual-channel temporal projection and rotation augmentation, symbol-level node features were obtained through data augmentation and feature extraction, and signal topological relationships were jointly modeled through a learnable adjacency matrix, graph coarsening, and dynamic graph attention aggregation. Tests were conducted on the RadioML2016.10a dataset, and the average recognition accuracy within the tested signal-to-noise ratio range was improved over baseline methods, while both the number of trainable parameters and floating-point operations remained low. The results show that the proposed method effectively reduces model complexity while maintaining high recognition accuracy, meeting the requirement for lightweight deployment of automatic modulation classification in intelligent spectrum monitoring scenarios.