On the imaging of biogenic and anthropogenic surface films on the sea by radar sensors

摘要: Radar signatures of sea surface films different origin are investigated, which have been acquired by airborne and spaceborne multi-frequency/multi-polarisation microwave sensors during the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture (SIR-C/X-SAR), missions in 1994, as well ERS SAR 1996–98. During SIR-C/XSAR, controlled film experiments were performed German Bight deploying various quasi-biogenic substances mineral oil on surface, order to study radar caused visco-elastic properties. In general, our results show that multi-frequency capabilities, rather than multi-polarisation needed for a radar-based system discrimination marine films. We that, under high wind conditions (> 10 m s−1), between kinds is very difficult, whereas at low moderate speeds (≤ 5 s−1) seems be possible. This finding supported analytically means new model wave number-dependent contrast statistically through analyses more 700 images. addition, laboratory presented carried out wind-wave tank University Hamburg. At certain wind-speed ranges damping bound freely propagating waves monomolecular observed, may explain contrasts measured sensors.