A New Strategy to Constrained Focusing in Unknown Scenarios

Abstract

We introduce a novel strategy to synthesize an antenna array capable to focus a field in an unknown scenario. The underlying power synthesis problem is efficiently solved via convex programming and using an approximation of the fields radiated by the array elements. This approximation stems from an original exploitation of the equation underlying the Linear Sampling Method. As such, the proposed strategy takes advantage of the broad applicability of this well-known imaging approach. Some numerical examples are given to illustrate the performance of the strategy.

An Algebraic Solution Method for Nonlinear Inverse Scattering

“…In particular, one can exploit the improvements that have been recently achieved in the capability of estimating the shape of the unknown targets [8], as well as the possibility of improving the focusing achieved via LSM by resorting to an ex-post constrained convex optimization [29]. Furthermore, future work will also aim at exploiting the method, or better its underlying concepts, in the more challenging case of vectorial fields and 3-D scenarios, where its features would become even more important.…”

“…As a matter of fact, determining the required superposition coefficients corresponds to the problem of focusing an electromagnetic wave in an unknown environment. This is a sort of canonical problem, which has been broadly addressed in the literature by means of various approaches, including the linear sampling method (LSM) [3], [6], adaptive time reversal procedures [26]- [28] or convex optimization synthesis methods [29].…”

Microwave imaging via iterated virtual experiments

“…On the other hand, once collected, this amount of independent information can be re-organized in a different way by taking advantage from the linearity of the scattering phenomenon. Starting from this simple linear 'transformation' of the scattering data, the concept of VE has been introduced in [6][7][8][9][10][11]. VE represent a re-arrangement of the original experiments (or originally collected information) and they do not require additional measurements.…”

“…Recently, a new linear approximation, which relies on the emerging framework of the virtual scattering experiments (VE) [6][7][8][9][10][11] and significantly outperforms the usual BA, has been introduced in [6]. As for the above referenced Born Approximations, also this approach can be extended to the case of partially known non-homogeneous scenarios, where it is expected to be able to deal with a range of profiles going beyond the validity of the Distorted Born Approximation (DBA).…”

Three-dimensional power focusing and shaping for effective hyperthermia treatment planning

“…To overcome this drawback, we have proposed an approach in which the diagnostic stage, rather than pursuing an image of the scenario, directly suggests how to realize (at least approximately) given fields in the unknown (or better partially unknown) scenario [9], [10]. Then, thanks to such an implicit The 8th European Conference on Antennas and Propagation (EuCAP 2014) 978-88-907018-4-9/14/$31.00 ©2014 IEEE patient-specific knowledge, the focusing problem is again successfully tackled by means of the OCPF approach.…”