Large Metasurface Aperture for Millimeter Wave Computational Imaging at the Human-Scale

Area of Science:

• Millimeter-wave imaging
• Metasurface technology
• Computational imaging

Background:

• Holographic imaging systems often face challenges with size and computational complexity.
• Metasurfaces offer novel ways to manipulate electromagnetic waves at millimeter wavelengths.

Purpose of the Study:

• To demonstrate a low-profile holographic imaging system at millimeter wavelengths.
• To reconstruct diffraction-limited images of human-sized subjects using frequency-diverse metasurfaces.

Main Methods:

• Utilized an aperture composed of frequency-diverse metasurfaces.
• Employed a single microwave source swept over a frequency band (17.5-26.5 GHz).
• Switched between transmit and receive metasurface panels, measuring spatially diverse field patterns.

Main Results:

• Successfully reconstructed diffraction-limited images of human-sized subjects.
• Developed computational methods and calibration approaches to address scaling challenges.
• Enabled rapid and accurate imaging performance for electrically large, coherent apertures.

Conclusions:

• The demonstrated system offers a viable low-profile solution for millimeter-wave holographic imaging.
• Advanced computational techniques are crucial for high-fidelity image reconstruction in such systems.
• This approach overcomes inherent scaling challenges in computational imaging.