Depth-of-focus issues on spaceborne very high resolution SAR

Higher resolutions mean a more complex challenge on the SAR imaging not only in dealing with an at least quadratically growing data amount, but the more with stronger conditions on the focusing of the SAR image. In this study the defocusing effect is evaluated quantitatively by measuring the resulting resolution of a simulated ideal point scatterer depending on its height distance to the focusing plane. The simulations indicate a linear dependence of the depth-of-focus on the square of the nominal cross range resolution.