Spaceborne Cooperative Detection for Distributed Sensing: Overcoming Inter-Satellite Link Limitations via Deep Information Bottleneck

We consider the cooperative detection for distributed sensing via low Earth orbit constellations. The source data gathered by the ground sensors are non-orthogonally sent to satellite access points, and then aggregated at a central satellite via inter-satellite links (ISLs). To overcome the intrinsic ISL bandwidth limitation, we consider the deep auto-encoding paradigm to jointly design the ISL transceivers among satellites, and propose a novel deep variational information bottleneck (DVIB) method which maximizes the end-to-end sensing accuracy under bandwidth constraints. Specifically, the mathematically untractable ISL bandwidth constraint is first transformed into an entropy-based format. Then a customized batch-norm layer is introduced, where the messages on ISLs are considered as latent variables and are regularized with entropy-constrained posterior for efficient compression. Compared to the benchmark, the proposed DVIB method is shown to simultaneously reduce the bandwidth overhead by 30% and enhance the sensing accuracy by 2-5 dB, validating the significance of relevant information extraction on ISLs.