Vurdering av ENVISAT ASAR for skipsdeteksjon
Abstract
Ship detection and monitoring has become one of the first operational services from civilian spaceborne Synthetic
Aperture Radar. The Norwegian Coast Guard presently uses such data to support fisheries monitoring in Northern
waters. The dual-polarised AP mode of the Advanced Synthetic Aperture Radar deployed on ENVISAT provides a
novel capability to extend the range of useful incidence angles for ship detection. At steep incidence angles, crosspolarised
images provide much improved ship to sea contrast ratios, compared to conventional co-polarised images.
Using cross-polarised data in one channel and co-polarised data in the second, one may also obtain combinations of
high contrast ship images in one channel as well as useful images of ship wakes in the second channel.