Active and passive millimeter- and sub-millimeter-wave imaging

Sensor Technology at Submillimeter Wavelengths for Space Applications

“…Recent progress in submillimeter-wave and terahertz (THz) technology, as well as the demand for new surveillance capabilities, has led to the development of prototype submillimeter imagers capable of detecting weapons concealed within clothing or packages [25][26][27][28][29]. Imaging in the submillimeter wavelengths is attractive because wavelengths in the range 100 μm < λ < 1 mm are short enough to provide high resolution with modest apertures and long enough to penetrate materials such as cloth or cardboard.…”

Remote respiration and heart rate monitoring with millimeter-wave/terahertz radars

“…Active mmw/THz imaging systems for applications such as concealed weapon detection [3] can also be used to simultaneously monitor subtle motion of the individual that relates to cardiopulmonary activity. In conjunction with other methods, these systems can improve force protection and provide the ability to assist in the detection of any suspicious individuals approaching a checkpoint or a secured facility.…”

600 GHz Imaging Radar with 2 cm Range Resolution

“…Imaging systems at millimeter and submillimeter wavelengths are actively being developed in response to the demand for new capabilities in surveillance and concealed weapons detection [1][2][3][4]. Strong molecular responses to THz radiation is also a driver for this technology, with applications in biomedicine and Earth and planetary science [5].…”