Shaping Microwave Fields using Non-Linear Unsolicited Feedback: Application to Enhanced Energy Harvesting

Abstract

Wavefront Shaping has emerged over the past decade as a powerful tool to control wave propagation through complex media, initially in optics and more recently also in the microwave domain with important applications in telecommunication, imaging and energy transfer. The crux of implementing wavefront shaping concepts in real life is often its need for (direct) feedback, requiring access to the target to focus on. Here, we present the shaping of a microwave field based on indirect, unsolicited and blind feedback which may be the pivotal step towards practical implementations. With the example of a radiofrequency harvester in a metallic cavity, we demonstrate tenfold enhancement of the harvested power by wavefront shaping based on non-linear signals detected at an arbitrary position away from the harvesting device.

6 pages, 4 figures

References in corpus (13)

• Image Transmission Through an Opaque Material
• Phase control algorithms for focusing light through turbid media
• Universal optimal transmission of light through disordered materials
• Control of light transmission through opaque scattering media in space and time
• Reference-less measurement of the transmission matrix of a highly scattering material using a DMD and phase retrieval techniques
• Noninvasive nonlinear imaging through strongly-scattering turbid layers
• Deterministic control of broadband light through a multiply scattering medium via the multispectral transmission matrix
• Spatio-temporal wavefront shaping in a microwave cavity
• The Single-Channel Regime of Transport through Random Media
• Principal modes in multimode fibers: exploring the crossover from weak to strong mode coupling
• Experimental Width Shift Distribution: A Test of Nonorthogonality for Local and Global Perturbations
• Nonlinear Time-Reversal in a Wave Chaotic System
• Optimal spatiotemporal focusing through complex scattering media