| Synthetic Aperture Radar (SAR), operating from spacecraft or aircraft, produces high resolution images of large ocean areas. Detection of ocean surface waves is usually possible from SAR images. One major problem in the production of SAR images is that the radar signal data require a great deal of processing. Another problem is that SAR images are sometimes degraded due to the motion of the ocean surface. A much better approach to extracting these wave parameters would be to estimate them from the SAR signal rather than the processed images. Here we present a new method which estimates these parameters from the SAR signal. The advantages of the proposed new method include: (1) the implementation is much simpler; (2) detailed knowledge of SAR system parameters is not required; and (3) ocean surface motion acts to emphasize the dominant wave. Here we report on results from the Point Arguello experiment where an ocean area off the coast of Point Arguello, California, was imaged from eight different aspect angles to determine the SAR response to ocean waves viewed from different aspect angles. Also we report on results from SEASAT JASIN experiment which took place during the summer of 1978 off the coast of Scotland. The ability of the space-borne SAR to image ocean surface waves is discussed. The dependence of SAR ocean waves measurements on different ocean surface parameters like wind speed, significant waveheight and waveslope is also studied. |
