The Response of Synthetic Aperture Radar to Ocean Surface Waves
Basic concepts of SAR imaging theory of ocean surface waves are reviewed. The effects of orbital velocity and acceleration on the imaging mechanism are discussed in simple physical terms. The spatially varying orbital velocity contributes to the imaging through “velocity bunching,” while the effect is relatively small and still in the linear range, but produces nonlinear image distortions and smearing for larger orbital velocities. The spatially varying orbital acceleration results in a nonuniform azimuthal image smear. Image contrast enhancement by azimuthal focus adjustment of the SAR processor is attributed to this spatial variability of the orbital acceleration effects.
KeywordsSynthetic Aperture Radar Synthetic Aperture Radar Image Ocean Wave Orbital Velocity Chirp Rate
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- Alpers, W. R., and C. L. Rufenach (1980): Image contrast enhancement by applying focus adjustment in synthetic aperture radar imagery of moving ocean waves. SEASAT-SAR Processor, ESA SP 154, ESA Sci. Tech. Publ. Br., ESTEC, Noordwijk, The Netherlands, 25–30.Google Scholar
- Hasselmann, K. R. K. Raney, W. J. Plant, W. Alpers, R. A. Shuchman, D. R. Lyzenga, C. L. Rufenach, and M. J. Tucker (1985): Theory of SAR ocean wave imaging: A MARSEN view. J. Geophys. Res. 90 (in press).Google Scholar
- Kelly, E. J., and R. P. Wishner (1969): Matched-filter theory for high velocity accelerating targets. IEEE Trans. Mil. Electron. Syst. MES-5, 98–105.Google Scholar
- Rufenach, C. L., and W. Alpers (1981): Imaging ocean waves by synthetic aperture radars with long integration times. IEEE Trans. Antennas Propag. AP-27, 725–729.Google Scholar
- Shuchman, R. A., E. S. Kasischke, and A. Klooster (1978): Synthetic aperature radar ocean wave studies. Final Report No. 131700–3-F.Google Scholar
- Environmental Research Institute of Michigan, Ann Arbor. Swift, C. T., and L. R. Wilson (1979): Synthetic aperture radar imaging of ocean waves. IEEE Trans. Antennas Propag. AP-27, 725–729.Google Scholar
- Teleki, P. G., R. A. Shuchman, W. E. Brown, W. McLeish, D. B. Ross, and M. Mattie (1978): Ocean wave detection and direction measurements with microwave radar. Oceans ‘78, Sept. 6–8, 639–648.Google Scholar
- Tucker, M. J. (1981): The ability of satellite-borne synthetic aperature radar to measure sea waves: The effects of sea surface motions. Working paper, January.Google Scholar
- Valenzuela, G. R. (1980): An asymptotic formulation for SAR images of the dynamical ocean surface. Radio Sd. 15, 105–114.Google Scholar