The Effect of Sea Surface Slicks on the Doppler Spectrum Width of a Backscattered Microwave Signal

Sensors

Vladimir Karaev¹  Mikhail Kanevsky² 

[1] id="af1-sensors-08-03780">Institute of Applied Physics, Russian Academy of Science, 46 Ulyanov Str., Nizhny Novgorod, 603950, Russ

关键词: remote sensing;    ocean surface;    slick;    microwave radar;    Doppler spectrum;   

DOI  :  10.3390/s8063780

来源: mdpi

【 摘 要 】

The influence of a surface-active substance (SAS) film on the Doppler spectrum width at small incidence angles is theoretically investigated for the first time for microwave radars with narrow-beam and knife-beam antenna patterns. It is shown that the requirements specified for the antenna system depend on the radar motion velocity. A narrow-beam antenna pattern should be used to detect slicks by an immobile radar, whereas radar with a knife-beam antenna pattern is needed for diagnostics from a moving platform. The study has revealed that the slick contrast in the Doppler spectrum width increases as the radar wavelength diminishes, thus it is preferable to utilize wavelengths not larger than 2 cm for solving diagnostic problems. The contrast in the Doppler spectrum width is generally weaker than that in the radar backscattering cross section; however, spatial and temporal fluctuations of the Doppler spectrum width are much weaker than those of the reflected signal power. This enables one to consider the Doppler spectrum as a promising indicator of slicks on water surface.

【 授权许可】

CC BY   
© 2008 by the authors; licensee Molecular Diversity Preservation International, Basel, Switzerland.