Adaptive millimeter-wave synthetic aperture imaging for compressive sampling of sparse scenes

Area of Science:

• Electromagnetics and Wave Propagation
• Signal Processing
• Radar Systems Engineering

Background:

• Locating sparse metallic objects is crucial in various applications.
• Traditional methods like raster scanning can be inefficient for high-resolution searches.
• Frequency Modulated Continuous Wave (FMCW) RADAR offers high-resolution capabilities.

Purpose of the Study:

• To develop and evaluate an adaptive sensing technique for precise localization of sparse metallic scatterers.
• To improve the efficiency of target detection using RADAR.
• To achieve sub-wavelength accuracy in scatterer positioning.

Main Methods:

• Utilized a high-resolution, frequency modulated continuous wave (FMCW) W-band RADAR system.
• Employed a single detector, frequency-stepped source, and lateral translation stage.
• Applied inverse synthetic aperture RADAR (ISAR) reconstruction techniques with an adaptive algorithm for sampling location determination.

Main Results:

• Successfully identified the two-dimensional location of one or two wire scatterers.
• Achieved sub-wavelength accuracy in scatterer localization.
• Reduced the number of lateral steps required by up to 75% compared to a simple raster scan.

Conclusions:

• Adaptive sensing significantly enhances the efficiency and accuracy of sparse metallic scatterer localization.
• The developed technique offers a substantial improvement over conventional scanning methods.
• Further research is needed to explore applications to more complex scattering geometries.