The EU FP7 project CONSORTIS (Concealed Object Stand-Off Real-Time Imaging for Security) is developing a demonstrator system for next generation airport security screening which will combine passive and active submillimeter wave imaging sensors. We report on the development of the 340 GHz 3D imaging radar which achieves high volumetric resolution over a wide field of view with high dynamic range and a high frame rate. A sparse array of 16 radar transceivers is coupled with high speed mechanical beam scanning to achieve a field of view of ~ 1 x 1 x 1 m 3 and a 10 Hz frame rate.
Atomic layer deposition (ALD) is
a viable method for depositing
functional, passivating, and encapsulating layers on top of halide
perovskites. Studies in that area have only focused on metal oxides,
despite a great number of materials that can be made with ALD. This
work demonstrates that, in addition to oxides, other ALD processes
can be compatible with the perovskites. We describe two new ALD processes
for lead sulfide. These processes operate at low deposition temperatures
(45–155 °C) that have been inaccessible to previous ALD
PbS processes. Our processes rely on volatile and reactive lead precursors
Pb(dbda) (dbda = rac-N
2,N
3-di-tert-butylbutane-2,3-diamide)
and Pb(btsa)2 (btsa = bis(trimethylsilyl)amide) as well
as H2S. These precursors produce high quality PbS thin
films that are uniform, crystalline, and pure. The films exhibit p-type
conductivity and good mobilities of 10–70 cm2 V–1 s–1. Low deposition temperatures
enable direct ALD of PbS onto a halide perovskite CH3NH3PbI3 (MAPI) without its decomposition. The stability
of MAPI in ambient air is greatly improved by capping with ALD PbS.
More generally, these new processes offer valuable alternatives for
PbS-based devices, and we hope that this study will inspire more studies
on ALD of non-oxides on halide perovskites.
The need for improved security at airports with high detection performance, high throughput rates and an improved passenger experience is motivating research into new sensing technologies. The European Union funded CONSORTIS project is addressing these aims by demonstrating a system which combines a submillimeter wave radar, a dual-band passive submillimeter wave camera and automatic anomaly detection software for reliable detection while ensuring passenger privacy. In this paper we describe the 340 GHz 16-channel FMCW radar which produces 3D maps of the subject with ~1 cm 3 voxel resolution over a 1 m 3 sense volume at multi-hertz frame rates. The radar combines advanced transceiver electronics with high speed mechanical beam steering and parallelized processing to achieve this level of performance. I.
We have completed a 16-channel 340 GHz 3D imaging radar for next-generation airport security screening under the European Union funded CONSORTIS (Concealed Object Stand-Off Real-Time Imaging for Security) project. The radar maps a 1 x 1 x 1 m 3 sense volume with ~1 cm 3 voxel resolution at multi-hertz frame rates. The radar has been installed in the CONSORTIS system enclosure and integrated with a passenger control system and command module. The full system will ultimately also incorporate a dual-band passive submillimeter wave imager and automatic anomaly detection software for reliable, ethical detection of concealed objects. A large data collection trial on targets of interest has been conducted to support the development of automatic anomaly detection software. Initial threat detection analysis indicates promising results against aviation-relevant objects including simulant dielectric threat materials.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.