Spaceborne Synthetic Aperture Passive Imaging Technology for Wide-Area Electromagnetic Spectrum Map Generati

Current space-based electromagnetic spectrum sensing and imaging methods suffer from several limitations, including inadequate acquisition and characterization of holistic situational information for radiation source clusters, inherent contradiction between field of view and resolution, and insufficient dynamic real-time sensing capability. To address these challenges, this paper innovatively applies the synthetic aperture passive interferometric imaging method, originally used in geographical and oceanic remote sensing, to the domain of spaceborne electromagnetic spectrum sensing, proposing a spaceborne synthetic aperture passive interferometric imaging technology for wide-area electromagnetic spectrum map generation. At the theoretical level, we establish a system model encompassing "radiation source signal emission- free space propagation- spaceborne synthetic aperture passive interferometric imaging", and analyze the differences between the radiation source signal and the background spontaneous emission during model establishment and synthetic aperture imaging processes in detail. For array configuration, we adopt a staggered Y-shaped synthetic aperture comprising 36 elements and define its placement and imaging perspective when deployed on a satellite platform. The experiments establish a dynamic simulation scene, incorporating three types of imaging errors with corresponding correction procedures. During phase error correction, this article introduces a robust covariance estimation via low-rank approximation (RCEVLA) method, significantly improving phase correction accuracy under anomalous signal interference. The simulation achieves high-precision, high-resolution, wide-field, real-time direct imaging of terrestrial radiation source electromagnetic spectrum.