Data-Efficient ConvNeXt Pretraining for High-Resolution Sentinel-1 GRD SAR Representation Learning
SparK-SAR is a sparse convolutional masked pretraining framework using ConvNeXt to learn from limited Sentinel-1 Ground Range Detected (S1GRD) data efficiently. It introduces a domain-adapted encoder and lightweight decoder that significantly outperform frozen Vision Transformer models with fewer parameters, showing that classification performance saturates quickly with less data.