This article deals with the large problem of interferometric synthetic aperture. Our analysis begins with the study of transverse distance influence and the orientation of the interferometric baseline. The processing of elevation problem solving relative to the horizontal resolution of conventional synthetic aperture radar has been carried out, including its ambiguity to choose the optimum parameters of the interferometer and thus improve the surface topography. We found out indeed that when we take a picture of the earth's surface at an angle of inclination of the baseline alpha = pi/4, the best results are obtained. Copyright (C) 2016 John Wiley & Sons, Ltd.