L. Shemer, ON THE FOCUSING OF THE OCEAN SWELL IMAGES PRODUCED BY A REGULAR AND BY AN INTERFEROMETRIC SAR, International journal of remote sensing, 16(5), 1995, pp. 925-947
Focusing of a monochromatic ocean wave image by either a regular or an
interferomeric SAR (INSAR) is studied. The model developed simulates
the images of both SAR and INSAR for an arbitrary focus setting. The e
ffects of the various operational parameters, i.e., integration and sc
ene coherence times, ocean wave length, direction and amplitude, etc.,
on the focus sensitivity of both SAR and INSAR is examined. A dimensi
onless focusing parameter a which depends on the platform velocity and
on the azimuthal component of the phase velocity of the imaged ocean
wave is introduced. It is shown that a is the major parameter which de
termines the image contrast of the regular SAR output, as well as that
of the magnitude and the phase components of INSAR. The focus sensiti
vity, however, is also a function of the imaged ocean wave parameters.
The effects of the varying SAR integration time and of the scene cohe
rence time on the contrast of the resulting image is also examined.