In this paper, a method to build equivalent models of radiating printed circuit boards based on complex E-field measurements taken in the close vicinity of the device under test is explored. It is shown that the inverse problem to be solved to retrieve the currents from the field data is ill-posed. An innovative regularization approach implementing a penalty on abrupt spatial variations of the currents is proposed to alleviate this difficulty. Various schemes to mesh the equivalent current distribution are also explored. Combining these with measurements, it is shown that accurate estimation of equivalent current models can be achieved, thereby allowing the identification of the emission sources. The method is tested for different circuit configurations with both synthetic and real data. Obtained results demonstrate the efficiency of the method.

This paper presents a contrast source inversion method for microwave tomography with improved performance with respect to the popular multiplicative regularized contrast source inversion (MR-CSI) method when the contrast of the object under study is relatively high. More precisely, some shortcomings of MR-CSI which may prevent it from performing adequately on higher contrast objects are outlined. The proposed method does not suffer from such shortcomings, but necessitates the tuning of parameters. However, a unique set of parameters can be used in a wide variety of experimental conditions related to a given application. Simple guidelines to determine their values are provided.

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In this paper, the advantages of planar Microwave Tomography (MT) applied to early stage breast cancer detection are presented. In the proposed planar configuration, the breast is compressed between two dielectric plates in a configuration similar to that of X-ray mammography. This approach would allow the future implementation of a dual modality imaging system where the advantages of both techniques can be exploited. The research efforts made both at DRÉ/L2S (Supelec) and Poly-grames (École Polytechnique de Montréal), for the development of a planar MT system are described, as well as, the key features of the latter. A numerical validation is used to show how the breast compression can lead to an enhancement of the reconstructed images.