Deals with the simulation of synthetic aperture radar (SAR) raw signal of actual ground sites described in terms of sparse input data. Since in most cases the input data reference system does not match SAR requirements, it is necessary to adopt appropriate interpolation schemes. The authors focus their attention on elevation input data, noting that natural surfaces exhibit fractal properties. Fractal and nonfractal interpolation schemes are discussed and applied. Simulated images are shown and compared to actual examples. Subjective and objective tests validate the simulation and support the fractal-based elevation interpolation.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>