Developments in the use and capability of millimetre wave technologies for stand-off detection of threat items over the last decade

The Home Office Centre for Applied Science and Technology (CAST) has a longstanding history in the evaluation of passive and active millimetre wave (mmW) systems for stand-off detection. The requirements for stand-off detection have evolved greatly over the last decade due to changes in threat, as has the capability of technologies. CAST has worked with these changes to evaluate systems alongside other government departments, developing expertise in the standard of technology from low to high technology readiness level (TRL) as well as understanding the limitations in detection. In this paper I discuss the work that has been undertaken by CAST since 2007, exploring the developments in methodology that have become necessary for trials to capture the requirements successfully. This involves utilising aspects of test protocols to ensure consistency across testing between CAST and other organisations, allowing for a fair comparison of data. The trials undertaken vary from evaluating the system capability in a static setting to the capability in a crowded environment such as a shopping centre. Understanding the performance capability of passive and active (mmW) systems in crowded places is particularly important given the current threat status of the UK.