Multiplexed measurement design for fixed Gantry x-ray computed tomography system (Conference Presentation)

X-ray Computed Tomography (CT) based systems are widely used for security and industrial inspection applications like passenger baggage and cargo screening at the airports, shipping container screening at ports, and industrial parts inspection. Typically, such CT systems employ a mechanical rotating gantry, with a X-ray source and detector array(s), to collect a large number of angularly diverse projections scans of an object. However, such a mechanical scanning mechanism adds to the system cost and maintenance. In this work, we consider the next generation Rectangular-Fixed-Gantry (RFG) CT system architecture containing several X-ray sources and detector arrays deployed in a fixed geometry. As such, such a RFG CT system architecture affords us the opportunity to explore non-standard multiplex measurement designs employing simultaneous illumination from multiple sources. The goal of our multiplexed measurement design is to minimize the bag reconstruction error (or Mean Square Error (MSE)) for a given source flux budget and/or fixed measurement time. We utilize a Bayesian Cramer-Rao Bound (CRB) on reconstruction error as a multiplex measurement design metric, subject to a fixed source flux/measurement time constraint. We find that the resulting optimized multiplexed measurement designs can significantly outperform the sequential measurement design employed in a traditional RFG CT system. We quantify this reconstruction fidelity improvement with multiplexed measurement design using simulation studies and assess its potential benefits in terms of operational system performance metrics such as bag reconstruction fidelity and system throughput.