Detection of buried objects: Tank experiments

Abstract

Detection and identification of buried objects in sediments is a wide problem which is far from being solved due to the complexity of the different situations encountered in real life applications (surface roughness, multiple reflections between object and water-sediment interface, complex nature and shape of the target, complex nature of the surrounding medium, porosity, bubbles). In these conditions, it seems hopeless to develop a general method capable of handling all these different situations. One issue for this problem is to resort to tank experiments and perfectly controlled situations. The aim of this paper is to give some answers to questions which frequently arise in detection problems of buried objects and also to show the limit of the assumptions which are made by most people working in this field. In particular, comments on the influence of the elastic behavior of the surrounding medium on the scattered field will be given; moreover, in the case of a simple shaped object, the shift in the position of resonances which is experimentally observed will be discussed. Finally, an experimental study of the influence of surface roughness will be given in order to show the importance of this effect on target detection.