On Solving Inverse Source Problems with Metasurfaces Performing Analog Computations

We investigate the feasibility of solving inverse source problems with metasurfaces that perform analog computations. In particular, we consider the antenna diagnostics application wherein the fields radiating from an antenna under test (AUT) interact with a metasurface system. The output fields of this metasurface system will then represent the tangential fields near the aperture of the AUT, making them suitable for diagnostics. To this end, we present a general design framework while highlighting the potential difficulties of these metasurfaces. We show via simulation data that the approach can work in principle, and also present how a cascaded system of metasurfaces could potentially provide a form of hardware-based regularization to treat the ill-posedness of the underlying problem.