IMAGING THZ RADAR FOR SECURITY APPLICATIONS

摘要

Detection of concealed threats is a key issue in publicsecurity. In short range applications, passive imagersoperating at millimetre wavelengths fulfill this task.However, for larger distances, they will suffer fromlimited spatial resolution. The paper describes the designand performance of 0.8-THz radar that will be capable toreveal concealed objects at a distance of more than 20meter with a spatial resolution less than 1 cm. The radarhighlights the scene with the built-in terahertz gas laserand uses heterodyne receiver with a singlesuperconducting hot-electron bolometric mixer and asolid-state local oscillator. With integration time of0.3 sec the receiver distinguishes a temperature differenceof 2 K at the 20 m distance. The field of view is sampledwith a high-speed conical scanner.