High resolution 3-D SAR via multi-baseline interferometry

The ability of interferometric SAR (InSAR) to provide terrain height estimation can be interpreted as being due to the baseline (of the two SAR imaging flight paths) acting as an aperture in the normal-to-slant-range (n&oarr;) direction. However, the aperture, because it consists of only two nodes, has effectively no resolving power. The authors introduce and examine a technique which synthesises an N>2 node aperture in the n&oarr; direction from N-1 connected baselines. This, together with the slant-range and azimuth resolving capability of SAR imaging systems, enables the generation of high resolution 3D imagery. A theoretical analysis and procedural outline of the proposed technique are presented