Deeply Sub-Wavelength Localization with Reverberation-Coded-Aperture

Abstract

Accessing sub-wavelength information about a scene from the far-field without invasive near-field manipulations is a fundamental challenge in wave engineering. Yet it is well understood that the dwell time of waves in complex media sets the scale for the waves' sensitivity to perturbations. Modern coded-aperture imagers leverage the degrees of freedom (DoF) offered by complex media as natural multiplexor but do not recognize and reap the fundamental difference between placing the object of interest outside or within the complex medium. Here, we show that the precision of localizing a sub-wavelength object can be improved by several orders of magnitude simply by enclosing it in its far field with a reverberant chaotic cavity. We identify deep learning as suitable noise-robust tool to extract sub-wavelength information encoded in multiplexed measurements, achieving resolutions well beyond those available in the training data. We demonstrate our finding in the microwave domain: harnessing the configurational DoF of a simple programmable metasurface, we localize a sub-wavelength object inside a chaotic cavity with a resolution of $\lambda /76$ using intensity-only single-frequency single-pixel measurements. Our results may have important applications in photoacoustic imaging as well as human-machine interaction based on reverberating elastic waves, sound or microwaves.

7 pages including 3 figures + 7 pages Supplemental Material

References in corpus (12)

• Light fields in complex media: mesoscopic scattering meets wave control
• Dynamics of Loschmidt echoes and fidelity decay
• High-sensitivity optical monitoring of a micro-mechanical resonator with a quantum-limited optomechanical sensor
• Resonant Metalenses for Breaking the Diffraction Barrier
• Reconfigurable Intelligent Surfaces for Rich Scattering Wireless Communications: Recent Experiments, Challenges, and Opportunities
• 6G White Paper on Localization and Sensing
• Universal Statistics of the Scattering Coefficient of Chaotic Microwave Cavities
• Transmission eigenchannels and the densities of states of random media
• On-demand coherent perfect absorption in complex scattering systems: time delay divergence and enhanced sensitivity to perturbations
• Fundamental bounds on the precision of classical phase microscopes
• Sensing Small Changes in a Wave Chaotic Scattering System
• Quantifying Volume Changing Perturbations in a Wave Chaotic System

Cited by in corpus (17)

• Reconfigurable Intelligent Surfaces for Rich Scattering Wireless Communications: Recent Experiments, Challenges, and Opportunities
• Meta-Programmable Analog Differentiator
• PhysFad: Physics-Based End-to-End Channel Modeling of RIS-Parametrized Environments with Adjustable Fading
• Intelligent Meta-Imagers: From Compressed to Learned Sensing
• Reflectionless Programmable Signal Routers
• Fundamental bounds on the precision of iSCAT, COBRI and dark-field microscopy for 3D localization and mass photometry
• XR-RF Imaging Enabled by Software-Defined Metasurfaces and Machine Learning: Foundational Vision, Technologies and Challenges
• Self-Adaptive RISs Beyond Free Space: Convergence of Localization, Sensing and Communication under Rich-Scattering Conditions
• Use of Transmission and Reflection Complex Time Delays to Reveal Scattering Matrix Poles and Zeros: Example of the Ring Graph
• Generative adversarial network for super-resolution imaging through a fiber
• Noise-Adaptive Intelligent Programmable Meta-Imager
• Optimal control of coherent light scattering for binary decision problems
• Non-Line-of-Sight Passive Acoustic Localization Around Corners
• High-availability displacement sensing with multi-channel self mixing interferometry
• A self-adaptive RIS that estimates and shapes fading rich-scattering wireless channels
• Deep learning estimation of complex reverberant wave fields by a programmable metasurface
• Reconfigurable Intelligent Surfaces in Dynamic Rich Scattering Environments: BiLSTM-Based Optimization for Accurate User Localization