Method for Estimating Clutter Limited Geosynchronous Synthetic Aperture Radar Performance

Abstract

This paper reviews the Geosynchronous Synthetic Aperture Radar (GeoSAR) literature and highlights a gap in land clutter theory. The gap concerns clutter models with weather dependence for incidence angles between 20 and 70 degrees. We update with an improved clutter model the System Performance method presented at IGARSS 2016 to estimate the SAR system performance taking into account the weather statistics and the landcover of the target area. The performance statistics obtained with this method allow to estimate the fraction of time (e.g. percentage of a month) in which the SAR system can accomplish the user's requirement. So far the method has been developed for short vegetation (specifically wheat), as source of clutter, and for bare land and urban area as other target areas. A full clutter model is still under development, but results are presented for the weather dependence of the coherent fraction of the scattered power. Since the azimuth spread of clutter power for GeoSAR can exceed the beam footprint in strong weather conditions, we expect improved image quality in these conditions. Two example of the effect of different clutter power Probability Density Function are briefly presented.

Physics-Based Clutter Model For Geosynchronous Synthetic Aperture Radar

“…The objective of this paper was to fill the gap in the clutter theory and thus allow the completion of the GEO SAR System Performance Assessment Methodology [1,2]. We presented a new physics-based clutter model for short vegetation landscape that is applicable to estimate GEO SAR performance, but is also suitable for a wide range of SAR systems.…”

“…For some GEO SAR mission concepts, the azimuth spread of the power scattered from clutter is a potentially important constraint on imaging performance because it smears a noise-like power across the image. Models of GEO SAR imaging therefore need to include clutter spread [1,2].…”