The effect of range-to-velocity ratio on simulated SAR images of ocean wind waves

Synthetic-aperture-radar (SAR) imaging of locally wind-generated ocean waves is simulated using the subwindowing technique. Several SAR range-to-velocity ratios (R/V) are used. Coherence is maintained throughout the imaging process, so the final image spectra include the noise resulting from phase-interference fading. Maximum spectral signal-to-noise ratio (SNR) is achieved with an R/V that maximizes velocity bunching modulation through imaging nonlinearities. Although the azimuthal shift of the spectral peak can be lessened by utilizing a lower R/V, the maximum wave number at which the signal exceeds the spectral noise does not change significantly, and the resulting decrease in overall S/N would probably make spectral extraction more difficult