190 GHz Millimetre-wave Imaging using MMIC-based Heterodyne Receivers

The capability of millimetre-wave imaging systems to detect concealed weapons and explosives is of interest to government agencies and the security industry. These systems generally operate at frequencies of 35 and 94 GHZ but there are significant advantages in moving to higher frequencies; particularly the possibility of increasing stand-off distance. In this paper a 190 GHz imaging system using MMIC-based heterodyne receivers is presented. These receivers exhibit a bandwidth of more than 20 GHz and, in conjunction with the 190 GHz transmitters also developed at CSIRO, may find applications in future high-capacity communication systems.