Security scanning devices based on electrical tomography, including
tomography systems based on the measurement of capacitance (ECT) and
electromagnetic tomography (EMT), in combination with knowledge-based
image analysis and understanding. Each device includes a sensing head or
transducer, sensing electronics, image reconstruction and image analysis
microprocessor (either microcontroller, DSP, laptop or desktop PC), a
display unit and accompanying software for identifying dangerous
materials and items. The security scanning devices enable enhancement of
image resolution with ECT and EMT. More sensors, more sensitive circuits
and flexible/optimal measurement protocols may be employed for obtaining
more independent measurements and enable implementation of data fusion to
combine the complementary sensitivity of ECT and EMT to different
material properties, while providing architecture to implement image
knowledge bases, which may characterize objects, whose image attributes
are acquired from multiple sensors.