@INPROCEEDINGS{Publ2012-408, author = {M. Kahl and A. Keil and J. Peuser and T. L{\"o}ffler and M. P{\"a}tzold and A. Kolb and T. Sprenger and B. Hils and P. Haring Bol{\'i}var}, title = {Stand-off real-time synthetic imaging at mm-wave frequencies}, booktitle = {Passive and Active Millimeter-Wave Imaging XV}, year = {2012}, volume = {8362}, number = {1}, pages = {836208}, publisher = {SPIE}, abstract = {We report on the development of an active stand-off imaging system operating in the 80 GHz~-- 110 GHz frequency range. 3D real-time imaging is enabled by a combination of a mechanically scanned one-dimensional conventional imaging projection with a rotating metallic reflector and a two-dimensional synthetic imaging reconstruction with a linear array of transmitter (Tx) and receiver (Rx) elements. The system is conceived, in order to allow a resolution better than 1cm both in lateral, as well as in range directions by using a multi-view imaging geometry with an aperture larger than 2 m x 2 m. The operation distance is 8.5~-- 9 m. The 2D synthetically reconstructed imaging planes are derived from the correlation of 20 sources and 24 coherent detectors. Range information is obtained by operating in a frequency modulated continuous wave (FMCW) mode. Real-time imaging is enabled by implementing the synthetic image reconstruction algorithms on a general purpose graphics processing unit (GPGPU) system. A multi-view imaging geometry is implemented, in order to enhance the imaging resolution and to reduce the influence of specular reflections.}, }