The simple theoretical model of Alpers and Hennings describing the radar imaging of submarine bottom topography in coastal waters with strong unidirectional tidal currents is analytically extended to show the influence of advection. The theory applies for L band radar, where second-order terms in the hydrodynamic interaction can be neglected as a first approximation. If future imaging radars from satellites and space platforms as the ERS-1 (First European Remote Sensing Satellite), the JERS-1 (First Japanese Earth Remote Sensing Satellite), and the EOS (Earth Observing System) are to be used for cartographic applications, it is necessary to include the effect of advection to improve accuracy. This extension of the model simulates the position of the radar cross-section modulation relative to coastal geomorphological bedforms. By application of that theory it is possible to map features such as the crest of sandbanks and sand waves. ¿ American Geophysical Union 1990