PASSIVE DETECTION APPARATUS

摘要

A passive detection device is disclosed comprising a plurality of antennas, receivers, and a digital beamformer, wherein the antennas and receivers are adapted to receive radiation of millimetre wavelengths from a near field region, to process and digitise it. The beamformer is adapted to process the received information and to generate static image information relating to the region. An indication means is provided to indicate the presence of objects of interest. The beamformer is preferentially adapted to generate information simultaneously in a plurality of planes at different distances from the apparatus. The indication means may comprise an array of pixels along the length of the apparatus to display image information, and may use the multi- planar information to construct images of the region comprising data from a plurality of planes. The invention has utility in security scanning applications such as at airports or other locations where security detection equipment is employed.