A fast target detection and imaging method for compressive sensing Earth observation

Abstract

The compressive sensing imaging technique, based on the realization of random measurement via active or passive devices (e.g., DMD), has attracted more and more attention. For imaging target of interest within large uniform scene (e.g., ships in the sea), high-resolution image was usually reconstructed and then used to detect targets, however the process is time-consuming, and moreover only part of the image consists of the targets of interest. In this paper, the stepwise multi-resolution fast target detection and imaging method through the combination of different numbers of DMD mirrors was explored. Low resolution image for larger area target searching and successively higher resolution image for smaller area containing the targets were reconstructed. Also, non-imaging fast target detection was realized based on the detector energy intensity, which includes the steps of rough target positioning by successively opening DMD blocks and accurate target positioning by adjusting the rough areas via intelligent search algorithm. Simulation experiments were carried out to compare the proposed method with traditional method. The result shows the area of the ships are accurately positioned without reconstructing the image by the proposed method and the multi-level scale imaging for suspect areas is realized. Compared with traditional target detection method from the reconstructed image, the proposed method not only highly enhances the measuring and reconstruction efficiency but also improves the positioning accuracy, which would be more significant for large area scene.