Information-theoretic analysis of fixed Gantry x-ray computed tomography transmission system for threat detection (Conference Presentation)

Detecting material anomalies in baggage requires a high-throughput X-ray measurement system that can reliably inform the user/classifier of pertinent material characteristics. We have developed a comprehensive high-fidelity simulation framework capable of modeling a multi-energy X-ray fixed gantry computed tomography transmission system. Our end-to-end simulation framework includes experimentally validated models of sources and detectors, as well as virtual bags to emulate the X-ray measurements generated by the fixed gantry X-ray CT system. This simulation capability enables us to conduct exploratory system trade-off studies around the current fixed gantry system, in terms of the source detector geometry, detector energy resolution and other relevant system parameters to assess their impact on the threat detection performance. Using scalable information-theoretic metrics, evaluated on simulated system data, we are able to provide quantitative performance bounds on the performance of the candidate system designs. In this work, we will report results of our initial system design trade-off studies focused on detector energy resolution and energy partitioning and how they impact the threat detection performance.