On the Problem of Focused Wave-beam Maximum Wireless Power Transfer beyond a Stratification

In this contribution, we state and discuss the problem of focused wave-beam maximum wireless transfer beyond a planar multilayer structure at microwaves and millimeter waves. Moving from a general analytical model of the problem, based on plane-wave expansion of the impinging wave-beam upon the stratification, the wireless power transfer efficiency is firstly defined and then maximized by changing beam relevant parameters. In addition, to preserve beam focalization beyond the multilayer, the problem is formulated in terms of a constrained optimization problem. As a special case, Bessel-shaped beams are considered as impinging beam on the multilayer. The applications of the proposed approach are quite broad, and span from microwave heating to through-the-wall radars.