%0 Journal Article
%T Location and Shape Reconstruction of 2D Dielectric Objects by Means of a Closed-Form Method: Preliminary Experimental Results
%A Gian Luigi Gragnani
%A Maurizio Diaz Mendez
%J International Journal of Microwave Science and Technology
%D 2012
%I Hindawi Publishing Corporation
%R 10.1155/2012/801324
%X An analytical approach to location and shape reconstruction of dielectric scatterers, that was recently proposed, is tested against experimental data. Since the cross-sections of the scatterers do not depend on the z coordinate, a 2D problem can be formulated. A closed-form singular value decomposition of the scattering integral operator is derived and is used to determine the radiating components of the equivalent source density. This is a preliminary step toward a more complete solution, which will take into account the incident field inside the investigation domain in order to provide the dielectric features of the scatterer and also the nonradiating sources. Reconstructions of the equivalent sources, performed on some scattering data belonging to the Fresnel database, show the capabilities of the method and, thanks to the closed-form solution, results are obtained in a very short computation time. 1. Introduction In the last decades, inverse electromagnetic scattering and near field imaging have been widely studied research topics [1]. Actually, electromagnetic imaging [2] is a very promising technique in many practical application fields. The more consolidated applications perhaps are those related to the use of ground penetrating radar, but a lot more are at present used or in advanced state of development. For example, it has been suggested that microwave imaging could be successfully used as a diagnostic technique in several areas, including civil and industrial engineering [3¨C5], nondestructive testing and evaluation [6¨C9], geophysical prospecting [10], and biomedical engineering [11¨C14]. Microwave imaging has also been proposed as a useful tool in wood industry [15]. Also, sophisticated techniques for plasma diagnostic can be based on microwave imaging [16]. Furthermore, inverse electromagnetic scattering can provide insights for approaching other problems of great interest nowadays, for example, plasmonic cloaking and the synthesis of metamaterials [17]. One of the aim of an inverse electromagnetic-scattering imaging system is to find the actual position of a dielectric object inside a bounded space region, as well as its shape. The techniques applied are based on the use of a known incident field illuminating the space region containing the object. By suitably measuring the scattered field, a solution to the problem can be derived. The main difficulties with solving an inverse electromagnetic-scattering problem result from its nonlinearity and instability. To overcome these negative features, in the scientific literature, several
%U http://www.hindawi.com/journals/ijmst/2012/801324/