Enhancing 3D Gamma-Ray Imaging with Through-Wall Radar

Detecting, localizing, and quantifying concealed nuclear material is a problem relevant to locating sources outside of regulatory control, containing contamination, and preventing illegal transport of radioactive materials. Recent advances include the ability to locate and quantify point sources in 3D more accurately by taking into account the attenuating materials between the source and a gamma-ray detector and by obtaining scene information through LiDAR measurements. These efforts have greatly improved the localization and quantification of obstructed sources, but they neglect internal structure composed of gamma-ray attenuating materials that LiDAR cannot detect. In this work, we report upon model-based efforts to advance the state-of-the-art by exploring the increased performance in quantitative gamma-ray imaging through the use of Through-Wall Radar Imaging (TWRI) to gain more information about the scene.