Compressive sensing (CS) is a new acquisition technique that can potentially open the way to multi- and hyper-spectral imaging in wide spectral regions with a simplified optical scheme. In this framework, we are studying different approaches applied to Earth observation in different contexts. We describe the design of a vis-NIR telescope, where the image sampling is performed in its focal plane with a Digital Micromirror Device (DMD), and the hyperspectral acquisition is made possible by a compact spectrometer with a multispectral detector. We show the approach for a pushbroom multispectral acquisition from space, working in both the visible and thermal bands, to monitor the status of the cryosphere. Finally, we describe a compact wideband system working in the 0.4- 2.5 micron spectral range, based on three parallel spectrometers, where the acquisition is performed with a pushbroom scanning and a rotating coding mask. Opportunities and constraints given by the CS approach in these different contexts are highlighted.
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