3D images have been produced from SAR data limited to curved aperture paths by imaging techniques usually associated with two dimensional image resolution enhancement. CLEAN and IMP/RELAX algorithms have produced images for two different measurement scenarios. Dynamic range of CLEAN images are dependent upon level sat which artifacts occur although valid scatterers appear below such levels. Artifacts occur due to focusing errors in IMP/RELAX images and in addition due to sidelobe leakage effects in CLEAN images. These are accentuated by the very large sidelobes of shallow apertures. Autofocused images are significantly sharper than those from initial aperture estimates. Methods to expand the processed image volume will extend the general usefulness of this technique as will methods to estimate and display subtle variations in fully populated 3D image volumes. For these purposes resampling of data onto a rectilinear grid may allow use of image estimation techniques already proven useful for 2D imaging.
Kenneth Knaell, Kenneth Knaell,
"Advances in three-dimensional SAR from practical apertures", Proc. SPIE 2845, Radar Processing, Technology, and Applications, (5 November 1996); doi: 10.1117/12.257222; https://doi.org/10.1117/12.257222