A unified theory on the focusing effect in SAR ocean wave imaging

Resolves the controversy surrounding the focusing phenomenon observed in the airborne SAR images of ocean surface waves. The translation of the wave pattern is shown to be responsible for introducing the degradation or defocusing of point images. The image enhancement therefore is a result of repositioning of the degraded point images, or refocusing of the defocused point images. The two theories are shown to be equivalent. The mechanism is illustrated through which the point images are defocused although scatterers do not physically move with the wave phase velocity. Further, by applying a correct approach to describing velocity bunching, it is shown that the principle applies irrespective whether the image modulation is by the radar cross section (RCS) or velocity bunching