Poster
in
Workshop: AI for Science: Scaling in AI for Scientific Discovery
Multi-Frequency Progressive Refinement for Learned Inverse Scattering
Owen Melia · Olivia Tsang · Vasilis Charisopoulos · Yuehaw Khoo · Jeremy Hoskins · Rebecca Willett
Keywords: [ Neural Networks ] [ inverse scattering ] [ recursive linearization ] [ Machine Learning ] [ inverse problems ]
Interpreting scattered acoustic and electromagnetic wave patterns is a computational task that enables remote imaging in a number of important applications, including medical imaging, geophysical exploration, sonar and radar detection, and nondestructive testing of materials. However, accurately and stably recovering an inhomogeneous medium from far-field scattered wave measurements is a computationally difficult problem, due to the nonlinear and non-local nature of the forward scattering process. We design aneural network, called Multi-Frequency Inverse Scattering Network with Refinement (MFISNet-Refinement), and a training method to approximate the inverse map from far-field scattered wave measurements at multiple frequencies. Our method is inspired by the recursive linearization method — a commonly used technique for stably inverting scattered wavefield data — that progressively refines the estimate with higher frequency content. MFISNet-Refinement outperforms existing methods in regimes with high-contrast, heterogeneous large objects, and inhomogeneous unknown backgrounds.