5. Antenna systems for millimeter imaging applications

5.1 Introduction and antenna specifications

Civil security applications for tracking people in need of rescue or considered dangerous, or for detecting weapons hidden on these people, in public environments such as airports or government buildings, are booming. While video surveillance cameras can already perform certain functions, they cannot detect weapons buried under clothing, or detect people buried after earthquakes, for example. One solution may therefore be to implement detection and/or imaging systems using "passive" or "active" electromagnetic wave systems. Passive systems are those which detect the natural radiation of objects or bodies, without first illuminating them, whereas active systems are radar systems which detect objects or people through the reflection of waves...