P1

In case of fixed geometry arrays, and for whatever upper bounds on the sidelobes, the optimal synthesis problem has been formulated and solved as a Convex Programming problem [1],[2]. As such, it does not require the exploitation of computationally-heavy global optimization procedures. The approach can be used as well in case one cannot define an array factor at all [3]. In both cases of spatially-symmetric linear and planar arrays the problem can be furtherly reduced to an even simpler Linear Programming problem, which also allows to argue about uniqueness (or lack of uniqueness) of a solution [4].
More recently, in collaboration with the National Research Council and the department of radiotherapy at the Erasmus MC in Rotterdam, the LEMMA Group showed how the approach can be effectively exploited in order to perform a spatial (rather than angular) focusing of the field in complex and realistic scenarios [5]-[11] (with application to the hyperthermia cancer therapy).

1. T. Isernia and G. Panariello, “Optimal focusing of scalar fields subject to arbitrary upper bounds,” Electronics Letters, vol. 34, no. 2, pp. 162-164, 1998. [click here]
2. T. Isernia, P. Di Iorio, and F. Soldovieri, “An effective approach for the optimal focusing of array fields subject to arbitrary upper bounds,” IEEE Transactions on Antennas and Propagation,vol. 48, no. 12, pp. 1837-1847, 2000. [click here]
3. L. Caccavale, F. Soldovieri, and T. Isernia, “Methods for optimal focusing of microstrip array antennas including mutual coupling,” IEE Proceedings-Microwaves, Antennas and Propagation,vol. 147, no. 3, pp. 199-202, 2000. [click here]
4. O. M. Bucci, L. Caccavale, and T. Isernia, “Optimal far-field focusing of uniformly spaced arrays subject to arbitrary upper bounds in nontarget directions,” IEEE Transactions on Antennas and Propagation,vol. 50, no. 11, pp. 1539-1554, 2002. [click here]
5. D. A. M. Iero, T. Isernia, A. F. Morabito, I. Catapano, and L. Crocco, “Optimal constrained field focusing for hyperthermia cancer therapy: A feasibility assessment on realistic phantoms,”Progress In Electromagnetics Research, vol. 102, pp. 125-141, 2010. [click here]
6. L. Crocco, L. Di Donato, D. A. M. Iero, and T. Isernia, “A new strategy to constrained focusing in unknown scenarios,” IEEE Antennas and Wireless Propagation Letters, vol.11, pp. 1450-1453, 2012. [click here]
7. L. Crocco, L. Di Donato, D. A. M. Iero, and T. Isernia, “An adaptive method to focusing in an unknown scenario,”Progress In Electromagnetics Research, vol. 130, pp. 563-579, 2012. [click here]
8. D. A. M. Iero, T. Isernia, and L. Crocco, “Focusing time harmonic scalar fields in non-homogenous lossy media: Inverse filter vs. constrained power focusing optimization,” Applied Physics Letters,vol. 103, no. 9, 2013. [click here]
9. D. A. M. Iero, T. Isernia, and L. Crocco, “Focusing time-harmonic scalar fields in complex scenarios: A comparison,” IEEE Antennas and Wireless Propagation Letters, vol. 12, pp. 1029-1032, 2013. [click here]
10. D. A. M. Iero, T. Isernia, and L. Crocco, “Constrained power focusing of vector fields: an innovative globally optimal strategy,”Journal of Electromagnetic Waves and Applications, vol. 29, no. 13, pp. 1708-1719, 2015. [click here]
11. G. G. Bellizzi, L. Crocco, G.M. Battaglia, and T. Isernia, “Multi-frequency constrained SAR focusing for patient specific hyperthermia treatment,” IEEE Journal of Electromagnetics, RF and Microwaves in Medicine and Biology, vol. 1, no. 2, pp. 74-80, 2017. [click here]